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Found 161 results

  1. Some Judith River IDs

    Here are some small fossils I found back in the summer of 2017 in Montana up in the Judith River Formation. 1. Small reptile vertebra? (.5 cm) 2. Assorted tiny bones several of which are likely from birds. 2a. Hollow at the broken end (about .8 cm). 2b. Hollow at both ends (1.2 cm). 2c. Hollow at both ends as well, looks like limb bone. (1.5 cm). 2d. Appears to be hollow on both ends (.7 cm).
  2. 2017 Wyoming Microsite Finds

    Last summer on my trip out west, I found these teeth at a Lance Formation microsite in Wyoming. Many of the fossils were found through splitting a yellowish-orange concretion filled matrix, while others were free from it. This site was on the same ranch where I found my theropod hand claw but in separate locality. It's rather late (EST) at the time I'm posting this but wanted to show some of the teeth I found and was hoping I could get some help identifying them. 1. Pectinodon bakkeri 2. Richardoestesia sp. (?) 3. Lizard/ Worn Herbivorous Dinosaur Tooth (?)
  3. Keeping track of tiny fossils has been difficult for me, but penny holders have been a real help. I have begun using picture frames to hold and display my fossils in penny holders. These frames are 5x7 inches. The primary use I have made of the holders is for small pieces of shale each of which contains a conodont.
  4. Bunch of micro-mollusks

    Hi all, A handful of days ago there was a sand pile right in my neighborhood. Not sure why it was there, probably someone was making constructions to their house, but in any case I was happy. That's because that kind of sand comes straight from the North Sea, which is full of Eemian fossil sediments! So I took a little plastic bag and spent an hour or two looking in that pile of sand for fossils. The very common Eemian bivalves came up abundantly (so species like Mactra plistoneerlandica, Cerastoderma edule, C. glaucum, Macoma balthica, etc), but that is not what I was too excited about. Seeing that the sand pile was rather small, it forced me to focus on just that little pile. Which is great, because therefore I actually started looking much more closely, and hereby also collecting tiny micro-fossils! Lots of gastropods, which is awesome because these are not as common as bivalves in these sediments. I namely found a complete yet puny Anomia ephippium, some very small Cerastoderma's, and also the ones attached. I would love to be able to bring these down to species level. So I am asking for your help! The Hague, Netherlands (from North Sea sediments) Eem Formation Eemian, Pleistocene; 120'000 y Thanks in advance, Max #1: Looks a little bit like Macoma balthica, but still a bit different... Very likely from the Tellinidae
  5. Since the upload of Part 1 succeeded, I'll now offer up Part 2, a look at two interesting taxa from the family Globigerinidae. This family contains most of the taxa that we associate with the idea of "planktonic forams", perhaps due to our familiarity with the "globigerina oozes" that form a significant part of the floor of the modern world oceans. Globigerinoides ruber (d’Orbigny, 1839) is one of the two “red” species of globigerinids, as the specific epithet indicates. It is well-known that the color of individual specimens varies from white to pinkish-red, and it is typically the case that only some of its globular chambers exhibit the red coloration. I have specimens with all white chambers, one red chamber, two red chambers, etc., and have a single individual that is all red. Interestingly, the intensity of the color seems to increase with the number of chambers affected, so the all red specimen is very red indeed -- it is also a little smaller than average. Here is a typical specimen seen from the umbilical side, in a slightly oblique view, showing the primary aperture and one red chamber: The genus Globigerinoides differs from Globigerina in that its species exhibit secondary apertures, formed at the junctions of the spiral suture with intercameral sutures: Here is the spiral side of the same specimen, again presented in an oblique view, with two supplementary apertures, two red chambers at the left, and a pale pink one at the right. The top, final chamber is white, as is most frequently the case. This taxon is the commonest foram in the sample, by a large margin. The other red globigerinid is Globoturborotalita rubescens (Hofker, 1956). According to the World Foraminifera Database, it also occurs in the Gulf of Mexico, but I have seen no specimens in my sample as yet. This taxon shows four chambers in the umbilical view, rather than three, and lacks the secondary apertures. A second interesting globigerinid, quite different from the preceding, is Globigerinella siphonifera (d’Orbigny, 1839). This genus exhibits planispiral forms, rather than trochospiral -- all of the chambers are in the same plane. (Actually, the test begins growth in a trochospire, but quickly switches growth pattern to planispiral.) There is a primary aperture at the base of the final chamber, and in fully mature specimens like this one, the initial chambers enter the final one through the primary aperture: The final chamber appears to be “gobbling up” the initial chambers, like the snake that swallows its own tail. In Part 3 of this entry, I’ll examine three taxa from the Family Globorotaliidae. Stay tuned.......
  6. Planktonic Foraminifera are particularly important in biostratigraphic studies and correlation, as they are ubiquitous in marine deposits, and evolve rapidly. They first appeared in Middle Jurassic time, and thus have a long geological history. There are many phylogenetic and correlational studies available, and their rapid evolution makes them exceptionally useful as temporal markers, or guide fossils. I am currently looking at planktonic Foraminifera from a deep-water sample that was collected from the Dry Tortugas Islands, off of the coast of southern Florida. The sample was dredged from a depth of 215 meters, due south of the islands. This is an interesting area, as it represents the eastern extremity of the Gulf of Mexico, as well as the northern edge of the Caribbean Sea. The sample is a very rich one, with numerous species of benthic Foraminifera, as well as a few ostracodes. There is a good selection of planktonic forams -- I have thus far identified ten species, and would like to discuss one of these, a member of the Family Pulleniatinidae. Pulleniatina obliquiloculata (Parker & Jones, 1862) is a rather unusual looking taxon, starting with a trochospiral growth pattern, but switching to a streptospiral pattern for its final chambers. It is globulose, and quite shiny, making it easy to recognize. It took me some time to locate a specimen for imaging, as most specimens have their aperture clogged with matrix. The aperture is low, but very broad, and the apertural surface of the chamber below it is strongly pustulose. If this image were rotated toward the viewer a bit it would be clear that a thin area just above the lip of the aperture (seen here as an imperforate band) also bears pustules, although they are not as strong as those beneath the aperture. For those interested in taxonomy, this species is the generotype of Pulleniatina. I am submitting this short blog entry to see if the recent problems with uploading to the forum have been fixed. If so, I'll be submitting other entries on this sample.
  7. The Lomita Marl Member of the San Pedro Formation is a well-known source for Middle Pleistocene marine fossils, and its beautifully preserved molluscan fauna has been treasured by fossil fanatics for decades. There are outcrops in the city of San Pedro, California, although many of the "classic" localities have been destroyed by urban development. It is well-exposed in the Lomita Quarry, located in the Palos Verdes Hills northwest of the city. It has been dated at 400,000 to 570,000 years ago, about equivalent to the Santa Barbara Formation, which occurs further north along the California coast near the city of the same name. The Lomita Marl is also an extremely rich source for microfossils, as ostracodes and forams are both very abundant and easy to extract from the matrix. Most taxa in these two groups are still extant off the southern coast of the state, but a significant proportion of the fauna appears to be extinct. (One must hedge here, as the ostracode fauna of the Pacific coast of the United States is not very well known; the forams are better documented.) A small sample of washed residues has given me the opportunity to begin study of this interesting fauna, and I hope to show some images of taxa from both groups on this blog. This first entry will look at four ostracode taxa, selected simply because they are relatively easy to identify. (Much of the ostracode fauna is known only in "open nomenclature", as in "Aurila sp. A", meaning that the species has not been recognized or is undescribed.) Bythocypris elongata Le Roy, 1943 is easy to recognize. It is common, and appears to be the only member of the genus to be found in the Lomita. It is a member of the family Bythocyprididae, which are smooth, and some would say "uninteresting" as a consequence. As is normal in the family, the anterior end of the valve is broader and a bit more inflated than the posterior end. The remaining three taxa are all members of the large family Hemicytheridae, a group with interesting surface ornamentation: Aurila driveri (Le Roy, 1943) is one of the several members of the genus to be found in the Lomita, and the only one (as far as I am concerned), that is easily recognizable. The high-arched dorsum and strong ventral flange place it in the large genus Aurila, and the prominent anterio-ventral teeth are characteristic only of this species. The caudal process is low on the posterior margin, and bears fine denticles. Australicythere californica (Hazel, 1962) is relatively large at roughly one millimeter in length, and is more elongate than most hemicytherids. There is no caudal process, but typically 3-4 large posterio-ventral teeth. The lower half of the anterior margin has some small denticles, rather worn on this specimen. The valve outline is quite distinctive for this species. Hemicythere hispida Le Roy, 1943 is probably the easiest ostracode from the Lomita to identify, and is quite abundant. This image does not do it justice, due to the lack of 3-D. Under a stereo microscope it looks almost "furry", as the entire valve surface is covered with round-ended tubercles. (The lack of 3-D here is due to the excess white matrix obscuring all but the ends of the tubercles.) This species also has a particularly prominent eye tubercle, seen here at the anterior edge of the dorsal margin -- under the microscope this tubercle appears somewhat shiny, rather like glass. (I had to sacrifice the shine to get decent illumination of the rest of the valve.) To make these images, the specimens were simply laid flat on the inside of the lid of a micromount box. Not very sophisticated, but it gives a nice black background -- at the expense of making the specimen a bit more difficult to illuminate evenly. And it's quick and simple........... That's it for this entry. I will try to illustrate some of the many forams to be found in the Lomita in a future blog entry.
  8. Here is my collection of small/micro fossils from the Arkona formation in Southern Ontario. Everything here was collected by soaking clay from the Arkona fm and sifting out the solid matrix. I'm sure many of my IDs are way off so please correct me and fill in the unknowns if you recognize anything! Tentaculites Bactrites sp. Left: Tornoceras sp. Right: Maclurites? sp. Left: Holopea? sp. Right: Nanticonema lineata Left: Hormotoma? sp. Right: Platyceras sp. Left: Scaphopods Right: Hyoliths Left: Paracyclas lirata Right: Prothyris? sp. Left: Nuculana rostellata Right: unknown Left: Nuculites triqueter Right: Nuculites pacatus Left: unknown Right: unknown Left: Spirifer sp. and Delthyris sp. Right: Chonetes sp. Left: Cyrtina sp. Right: Cyrtina sp. Left: Camarotoechia sp. Right: Camarotoechia sp. Left: Onniella trigona Right: unknown Left: Terebratula sp. Right: Productella spinulicosta Ostracods Left: Eldredgeops sp. Right: Eldredgeops sp. unknown blastoid Devonaster? sp. arm fragment crinoid fragments
  9. Hi, I've recently fully processed some matrix from the Lower Hamstead Mbr. that I collected back in November, and I thought I'd share some of my finds in a similar way to my Bembridge Marls Mbr. material. The matrix originates from a 'shelly' horizon in the Lower Hamstead Mbr. and was collected from fallen blocks at the base of a low cliff exposure at Bouldnor Cliff. The Lower Hamstead Mbr. overlays the late Eocene Bembridge Marls and dates from the very earliest Oligocene epoch, approximately 33.75 - 33.5 million years ago. To put the finds into an environmental context the Lower Hamstead Mbr. was deposited during a period of rapid global cooling and drop in sea levels associated with the onset of antarctic glaciation (Oi-1). The cooling and eustatic change had begun in the late Eocene, with the palaeo-environments of the Bembridge Marls becoming increasingly terrestrial towards the Eocene/Oligocene boundary. By the Lower Hamstead Member the southern Hampshire Basin was a low lying coastal plain with extensive wetlands, lakes, ponds and sluggish rivers flowing south east towards the early channel (at this time the channel was more a large embayment with only occasional connection to the North Sea). The dense sub-tropical forests of the late Eocene had disappeared and the landscape was dominated by open woodlands of pine, sequoia, and oak. The environment was much cooler and annual rainfall had significantly dropped since the Eocene, although temperatures would begin to rise again further into the rupelian and Hamstead Mbrs. The basin was surrounded by areas of chalk upland (still existing today) with forests of sequoia and broadleaf species. This dramatic climate change is likely what triggered the Grande Coupure, in which endemic Eocene mammals like the palaeotheres disappeared and were replaced with Asian groups such as carnivorans, rhinocerotids, anthracotheres, and a variety of other artiodactyls. The mammals of the dense tropical Eocene forests simply couldn't adapt fast enough to the new open environments of the Oligocene and ultimately failed to compete against the better adapted migrants. By the Upper Hamstead Member the mammals on the Hampshire Basin coastal plain are almost entirely of Asian origin. Therefore the micro-vertebrates lived in an environment of large scale climatic and ecological change, which I think adds another level of interest to collecting from this member of the Bouldnor Fm. The material I've collected so far is a lot more varied than the Bembridge Marls, but overall is less abundant. So far it's produced at least 3 fish taxa, 2 mammals, and an indeterminate piece of jaw which may be reptilian or mammal. 1. A skull element from a Bowfin (Amia sp.), these fish are very common in most horizons of the Bouldnor Fm. 2. A vertebra from a Bowfin (Amia sp.) 3. A damaged lateral scute from a Sturgeon (Acipenser sp.) showing the transition to a freshwater environment 4. An indeterminate piece of a tiny jaw, may be crocodilian although I'm not sure. 5. The nicest find of the lot, a lower incisor from the theridomyid rodent Isoptychus (ID'd by Jerry hooker from the NHM). These rodents looked similar to modern kangaroo rats, hopping along the ground on large rear legs. Bite marks on Isoptychus bones collected from Thorness Bay suggest that they were common prey for the bear-dog Cynodictis. 6. Finally 2 images of an unidentified mammal tooth. I'm unsure as to whether this is part of the tooth or the entire crown, but it doesn't appear to be from a rodent. Hope you all enjoyed the finds, Theo
  10. One of the problems I experience in studying microfossils is that of orienting a specimen so that crucial characters are visible. An example: for identification it is often necessary to check the shape of the tooth in the aperture of taxa in the family Hauerinidae. The tooth can be long or short, plain or bifid, present or missing, etc. The aperture is on the end of the test, so it isn't possible to look into it when the test is lying flat -- which it always does when the test is lying in a tray under the scope. Of course, it is possible to use a little glue on the opposite end and manipulate it into a vertical position: but this is a lot easier said than done! However, there is a much easier way to look at such things -- use a mechanical two-axis stage, which will allow you to turn a specimen to literally any position under the stereo 'scope. One of my holiday gifts this year was just such a stage, of the type most commonly used by entomologists to examine pinned insects. To use the stage, I have a size 0 insect pin from which I removed the head with side-cutter pliers. I put a small drop of gum tragacanth on the resulting blunt end of the pin, and touch it to the side of the specimen I wish to examine, where it quickly dries. I stick the sharp end of the pin into the soft rubber plug of the rotating arm of the stage, and I'm set to go. I can alter the orientation of the specimen by rotating either of the two axles of the stage; by rotating the whole stage around its vertical axis I get the third "axle". The pin is not too distracting, and only the little area under the glue is not visible. This works quite well! In this image, the aperture is at the upper end, toward the top. (Oops, mispelled "hauerinid", drat...) Two chambers are visible on this side, and there are three chambers visible on the opposite side. One can't see the tooth in the aperture, par for the course when the test is lying flat. Let's look at another specimen, mounted on the mechanical stage: I rotated this specimen by 90 degrees from its "flat" position, and now the aperture is perfectly placed for inspection. The long tooth in the aperture is clearly visible, as is the thickening of the lip. Another example using different orientations: here the specimen is perched on top of the pin. The genus Lenticulina is planispiral and involute, and the aperture is at the upper end of the exposed face of the final chamber. The aperture is radiate; i.e., composed of several thin slits in the shape of an asterisk. This can be difficult to see. In this image the position of the aperture is marked by the arrow, but the nature of the aperture is not at all clear. Rotating the test by 90 degrees to get a profile view gives us a better look, and this profile view is also most useful in species identification: In this image, the test is mounted on the pin, which is glued to the underside of the specimen. So why is the pin not visible? To light specimens under the 'scope I use a two-arm fiber optic illuminator -- careful adjustment of the twin light heads can "eliminate" the pin with shadows. (Any remaining reflections from the pin are easily removed with image processing software.) If the pin were visible, it would extend downward to the lower edge of the image. Eliminating the pin makes the specimen appear to "float in midair", but at the expense of a weakly illuminated underside. This image shows the involute structure nicely, the apertural face, the swollen center of the test, the thin peripheral keel, and the pale aperture area at the right end. The aperture itself is still not well revealed, however. Let's adjust the orientation a little more: Turning the right end of the test upward toward the objective lenses, and boosting the magnification a bit, brings the radiate aperture into better view. Three of the radial slits, filled with contrasting matrix, are fairly clearly shown. Further rotation upward toward the objectives would provide a fuller view of the aperture, but this view is sufficient to demonstrate that the aperture is indeed radiate in structure. This method of mounting a specimen on a pin is totally non-destructive: to remove the specimen from the pin one just immerses it in a drop of water, where the gum tragacanth will quickly dissolve, leaving the specimen completely undamaged. Hopefully this blog entry will encourage others to explore ways to alter the orientation of their specimens, whether for identification purposes or photo-imaging.
  11. Hi all, I think that this is my first time in this thread of the forum, after being active for about a year and a half... Shame on me! Well, just for your info I know absolutely NOTHING about microfossils. So please bear with me So I have a question for you guys: So I bought this microfossil slide recently for just 3,25€ (not sure if it’s a good deal or not, but seemed okay to me), thinking it would be useful to store my very small fossils. Well, when I got it, I had two surprises: 1) it’s a lot smaller than I thought it would be! Fossils can get REALLY small I guess! 2) there aren’t any walls or so separating each number square. I thought that this would be simply another one of these sorting boxes with different “sub boxes”, which are always useful for storing fossils appropriately; but then a mini version for microfossils. Seems like I was very wrong! So so my main question is: how do I use this? Also, if you have any tips on how to go around with microfossils appropriately o would be glad to hear them. Again, all this stuff is very new to me. Microfossils are definitely not my strong point. Thanks in advance, Max
  12. While picking specimens of Foraminifera from the Taylor Marl, of the Texas Cretaceous Gulfian Series, I found several fragments of a taxon that I could not recognize. However, today I found a nearly complete specimen of what is obviously the same organism. Frondicularia christneri Carsey, 1926 does not look much like a typical member of the genus. The overall shape of the test is fairly normal, but the sutures form a rather unusual pattern, and they are raised above the test surface and slightly thickened (limbate). The test is rimmed, and the sides are flat. (It is this rimmed edge which produces limbate sutures when additional chambers are added.) Note that the final chamber, bearing the terminal aperture, occupies the entire right edge of the test. (The lower left corner of the test has been broken away, which creates the obvious asymmetry.) This unusual structure is not unique within the genus, however; Michael's Foraminifera Gallery website shows at least one other taxon with the same type of limbate sutures. In his 1954 Handbook of Cretaceous Foraminifera of Texas, Frizzell transferred this species to the genus Kyphopyxa, a move that is neither cited nor recognized in the World Foraminifera Database. In her original description of the species, Carsey noted that it is more typical of the Austin Chalk, although not rare in the Taylor Marl. I have a sample of the Austin Chalk, and will be looking for this taxon when I get to it.
  13. Holiday greetings to all! This is just a notice that I'm reactivating my blog, Microfossil Mania!, with two new entries. More to come, mostly on the Texas Cretaceous and California Pleistocene and Miocene. Have a look if you are interested in forams and ostracodes. Rumi
  14. When I was preparing my previous entry on nodosariid forams from the Pecan Gap Chalk, I originally included a specimen that I had identified as a member of the genus Dentalina. This identification was incorrect, and I edited the entry to remove that specimen. Here it is again, with what I hope is the correct identification! The genus Strictocostella is a member of the family Stilostomellidae, and this species is illustrated in Frizzell's "Handbook of Cretaceous Foraminifera of Texas" as a member of the genus Stilostomella. He also listed it as occurring in the Pecan Gap Chalk. Better images can be found on the World Foraminifera Database -- they show specimens with some very small spines around the bases of each chamber, almost what one might call "hispid". The drawing in Frizzell does not show this feature, nor does my specimen. I have not yet looked at Cushman's original description, but I am reasonably confident that this difference is within the range of natural variation. (I have seen this kind of variation on images of other stilostomellids.) I like it when I "Live and Learn!" And I'm glad that I caught the error.............
  15. I have recently been studying a sample of washed residues from the Pecan Gap Chalk Formation of the Cretaceous Gulfian Series, from an outcrop in the vicinity of Austin, Texas. Most of the Gulfian formations are richly fossiliferous, and the Pecan Gap is no exception. It has abundant, well-preserved microfossils, particularly forams and ostracodes. In this blog entry I would like to show some forams of the family Nodosariidae, which I find of particular interest. All belong to the genus Frondicularia, which has compressed, biserial tests. Frondicularia archiaciana d'Orbigny, 1840 is one of the maddeningly similar "narrow" forms within the genus, whose identification often requires close attention to the contours of the test outline. The biserial growth form of the test appears in most members of the genus as inverted chevrons when the image is oriented with the aperture uppermost. This structure is more-or-less apparent depending on the relative transparency of the individual test, and it shows quite well in this image. What one is seeing are the suture lines between the chambers. The aperture in members of the Nodosariidae is radiate; this type of aperture does not stand up very well to post-depositional forces, and is very frequently broken away -- true of all four specimens in this entry. Frondicularia frankei Cushman, 1936 is one of a group of taxa within the genus in which the base of the test is not compressed. In profile, the base appears to be bulbous, with rather wide "ripples" oriented lengthwise. The upper 3/4 of the test is compressed, and appears quite flat in profile. The basal spine is one of the distinguishing characters of this species, although many others show such a spine also. Frondicularia intermittens Reuss, 1865 is another taxon of the "narrow" group, in which the chevrons produced by the biserial structure are less apparent. A few bright, length-wise streaks show that the sutures separating the chambers are depressed. The largest of the nodosariids that I have found thus far is Frondicularia mucronata Reuss, 1845. The larger, more ovoid appearance of this taxon is due in part to the greater length of the individual chambers, which also gives the "inverted chevron effect" a somewhat different character. The specific epithet is from the small basal tooth on the initial chamber (proloculus) of the test. Hopefully, readers have enjoyed looking at these little fossils. If so, stay tuned -- I'll be writing more about microfossils from the Texas Gulfian Series, and will also upload an entry on Pleistocene Ostracoda from the San Pedro Formation of California in the near future.
  16. World's oldest fossils ever

    The origins of life now date back to 3.5 billion years ago https://phys.org/news/2017-12-oldest-fossils-life-earth-began.html
  17. Hi, I thought I'd show some of my first micro-vertebrate fossils from the Bembridge Marls Mbr. of the Bouldnor Fm. I collected around 2kg of matrix from one of the 'shelly' estuarine horizons in the lower part of the member at Hamstead Ledge, and am really pleased the results so far! The Bembridge Marls form the basal member of the Bouldnor Fm. and were deposited between 34.0 and 33.75 million years representing the final 250,000 years of the Eocene epoch. The depositional environment varies throughout the member and many beds are laterally discontinuous (like the Insect Bed, which produces finely preserved insects, feathers, leaves, and lizard skin impressions). Generally however, the Bembridge Marls were laid down in a sluggish lagoonal/estuarine environment with areas of wetland and adjacent sub-tropical/tropical forests, in the southern regions of the Hampshire Basin. To the south were forested chalk uplands that are now the downs of the Isle Of Wight. There was also some fluvial influence from rivers flowing from the west, draining the uplands around Dartmoor in Devon. Fauna-wise vertebrates like fish and freshwater turtles are common, and mammal remains are rarely found (in comparison to the overlying Hamstead members which are rich in post and pre-grande coupure mammals), these include palaeotheres, creodonts, rodents, anoplotheres, choeropotamids, xiphodonts, and primates. So far I've only searched through a small amount of the matrix but it has produced indeterminate teleost vertebra, Bowfin teeth, fin spines, indeterminate fish premaxillae, and a very nice crocodilian tooth. (The quality of the images isn't always fantastic but I'm trying to find a way to work around it in the microscope's program) Isolated fish vertebra from teleosts are by far the most common micro-fossil, and I've collected more than 10 so far. Here's a nice example: Bowfin teeth are also quite common and vary in size from 2-7.5mm in length. Bowfins would have been ambush predators feeding on smaller fish and other vertebrates in the lagoons and estuaries. Based on vertebra I've found ex-situ on the beach it seems some of these fish were very large. (Close up of one the teeth) These pre-maxillae also seem to turn up from time to time and appear to be from some form of teleost. The closest match I can find is with some kind of Gadiform? And finally the best find so far, a crocodilian tooth crown. I spotted this on the surface of one of the matrix blocks. It's most likely from the alligatoroid Diplocynodon which was very common in the wetlands and rivers of Europe from the Palaeocene to the Miocene. Diplocynodon has also been found in the early Eocene marine deposits of the London Clay suggesting that they frequented both freshwater and brackish/coastal habitats. The matrix is nowhere near fully sieved and sorted through yet so hopefully there's a lot more micro-vertebrates in there! Hope this was of interest, Theo
  18. Hi, I collected some fossiliferous matrix yesterday from the Bembridge Marls Mbr. and Lower Hamstead Mbr. of the Bouldnor Fm. and was wondering if anyone could advise me on the best method to separate the clay from the micro-fossils. I've been interested in collecting micro vertebrate remains alongside the larger material for a while now and received a digital microscope for my birthday last week. I had a go at extracting some from some smaller pieces of matrix I collected last weekend (by simply washing the clay around in a bowl and then repeatedly decanting it) and produced a rodent incisor and various fish bones. I'm worried that just washing the clay around may destroy some of the fossils so I was wondering if there was a safer way to extract them that effectively separates the matrix from the fossils. The matrix itself is from estuarine facies, and is essentially clay that is heavily packed with gastropods, bivalve fragments, and vertebrate material (predominantly fish and crocodilians). Any help would be really appreciated, Theo
  19. Fenestrate bryozoan coral. Harpersville Fm., Brown County TX. 305 mya. Specimen is about 1 cm. across. The pores are about 0.5 mm in diameter. Taken with my new Google Pixel 2 XL and a Moment macro lens. The first pic was taken with the Moment 10x macro lens by itself. For the second I added a 52 mm filter adapter from Mad Dog Labs and a 10x diopter.
  20. What do each of y’all recommend as a good range of magnification for general microfossil use? I know if it’s to little it won’t make the image big enough to see, and if it’s to much, you will be “zoomed in” to much, and only see just part of the fossil. I have a 500X digital microscope that USB plugs into the computer. I don’t have a particular type of microfossil I’m targeting. Just getting into it. But the smaller ones I can see, the better. So so what is y’alls recomendations?
  21. This post will be ongoing as I am still processing my Oxford Clay and started looking at microfossils in it in 2009, I think. Hoping to start photographing finds very soon. See finds already donated to museum in Partners in Palaeontology - Contributions to Science. 1- Agglutinated foram 2 - Also Agglutinated foram according to museum, weird. Would like to find another photo to confirm. I think I need an Jurassic atlas on the things. Santa take note. Yes I will work out how to stack my microscope photos one day.
  22. A few months ago I put about a dozen tiny fossil inside of those empty gel caps you buy at high health for making your own "supplements" . the monsoon humidity got to them even inside the house, and the fossils inside got glued to the wall. Oh man, I saved them but wont use those again! Also, one gel cap that was in with a pile of small fossils in a box had micro fossils glued all over the outside of it. Those capsules at first seem a great idea, but unless you live in the Sahara, they are more trouble than they are worth. Any body else had this happen to them?
  23. Microfossil photography

    Hey everyone, I am wondering if anyone knows a professional microscope that can be used to photograph microfossils. I need to make pictures of fossils such as bonefish teeth, ptychotrygon teeth, etc, that are 2-3 mm big. Does anyone have any suggestions? Thanks for any help.
  24. New Microfossil microscope!

    HI all, Finally, after 20 years of using a cheap stereo microscope with cheap optics and base, we decided to get a new one with all the bells and whistles. Our back log of Fort Apache microfossils which we are studying at present was the catalyst for this. We got an awesome scope from AmScope, a trinocular unit with 3.5x - 90x range and a 10 Mpix built in camera. Its like going from watching a small TV to going to the IMAX theatre! What an awesome scope for $909. Here are my very first attempts at some images taken today, of some of the Fort Apache material. I set the camera for 5Mpix and resized the images here to 1290 x 960 which is like 1 mpixel to keep them within size limits, but you get the idea. The Trinocular feature puts light to the camera when you push or pull in a lever and sends the left eye to the camera instead. The camera and eyepiece can be set independently so you can get it pretty close by just focusing normally. Here are a few sample images. I have a lot to learn on microscope imaging, but the software that came with the camera is amazing. Two image scales here, one at 3.5x and another at 20x zoom. Three gastropods and a pinhead. 3.5x with LED side lighting. Now here at 20x is the same group but first with the LED side light: Now for comparison, using the Halogen Ring light: I dont like this very well, so Ill use the LED for fossils anyway. Fenestellid Bryozoan, 3.5x Bryozoan at 20x Tenticulites at 3.5x Now at 20x And here is the setup as it sits right now. The black lamp on its left is the LED high intensity light from Walmart. I have yet to try focus stacking and many other things. The camera was taken at 5mp and I can go much larger files but thats a bit of overkill. More to come!
  25. I wish to send my friend in the mail some specimens out of the acid bath of some super tiny gastropods that are like fly specks - so tiny that you need a microscope to see them. How should I do this so he can find them when they arrive? Im hoping for something from the hardware store, or locally.
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