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I'm starting to sort through the trilobites I found at Oak Springs and need some help. My degree is in electrical engineering, which means when I was in college I never had to take any of those pesky courses in biology, zoology, etc. But that puts me at a disadvantage now as I read through the descriptions of the candidate trilobites and try to make sense of them. There are a fair number of papers published on the trilobites of the Cambrian in California and Nevada. To help identify what I have collected I'm using this one: Carrara Formation. Here is where I am having difficulty. The descriptions in this paper include features that don't appear on the diagrams I have of trilobite morphology. I have compiled one example here: Gilberti.pdf (reproduced as a low-res JPEG below). The color photo at the top is the specimen I'm trying to identify. I think it might be an Olenellus gilberti, so I have pasted that description below the photo, along with three photos of O. gilberti from the paper. (Below those photos is a diagram of trilobite morphology I pulled from the Internet.) The description of O. gilberti includes at least two features that don't show up on the morphology diagram: occipital ring (is this the same as occipital lobe?) and intergenal spine (I don't think this is the same as genal spine?). More concerning to me is this part of the description: "Glabella elongate, separated from frontal border by preglabellar area as wide or wider than anterior border." In my novice opinion, the examples in photos 6-8 from the paper show glabellas that extend pretty much all the way to the anterior border. In my specimen the preglabellar area is much wider, which would seem to be more consistent with the written description. Any help would be appreciated. Of course I'd like to identify the specimen, but what I'd really like are pointers on how to interpret the morphology descriptions. Maybe I've got an O. fowleri instead of O. gilberti, but if I don't understand how to interpret the descriptions I won't be successful in identifying it. Is there a book I should lay my hands on?

My wife and I just got back from a 1700-mile road trip from our home in Northern California to do some trilobite hunting in Utah and Nevada. It was a 5-day trip, with a total of about 8 hours of digging spread across 2 days, but well worth it. I will give you the highlights here. After driving across California, we spent the first night in Reno, then headed out on Highway 50 toward the U-Dig fossil quarry out of Delta, Utah. We spent the second night in Ely, Nevada. Along the way, we stopped in Austin for lunch and helped the owner of a nearby trading post identify an unknown fish fossil they had for sale (you can read about that here). We got to U-Dig mid-morning of the third day and spent half a day there. The last 20 miles is a drive along a well-maintained dirt road (good enough that with my stock 4WD SUV I could drive 50-55 mph along most of it). Other people on this forum have posted about their experiences at U-Dig, so I won’t spend a lot of time repeating the basics. We were pleased with the support we got from Gene and if you’ve never been there, I would recommend it. This was my second time there (the first was 8 years ago), and my wife’s first time. I have to say we weren’t as successful as on my last visit, but still got a good haul. Most, however, were only molts or partials, we got very few full trilobites. I’ve included some photos below. Lots of prep work still remaining, and I’ll probably split several of the slabs again to see what else I might find. If you go, one word of advice. They will provide you with a chisel-edge rock hammer, a 2-lb sledge and large chisel, and a bucket to hold everything you find. I brought all my own stuff and am glad I did. They show you how to split the shale with the chisel edge of the hammer, but I found that to be a fairly coarse way to do it. I found it much easier to use thin rock-splitting chisels like these. They are cheap, so I’d recommend you take one or two along. The next day we headed out to Caliente, Nevada, to dig at the Oak Springs Trilobite Site just off Highway 93. There is no fee to dig here, which means there is no one to advise you, you’re on your own. This is another Cambrian site with the possibility of finding several species of Olenellus trilobites. We got there just after lunch and spent the afternoon there. The parking area is about a quarter mile from the highway down a good dirt road (but not a 50-mph road!). Most people park there and walk a quarter mile along a developed path to the dig. If you’ve done your homework, though, you’ll know you can continue another short distance and park just at the base of the swale where the trilobites are. That makes it an easy walk, especially if you are carrying a lot of tools. in addition to my tool bag, I was carrying a Harbor Freight pry bar and my brand new Estwing PaleoPick, so I was happy to shorten the walk. You can tell when you are at the site because it is littered with broken pieces of shale and there are potholes all around where people have been digging. We spent the first couple of hours without any luck as I moved from one location to another. Then I moved to yet another location and immediately saw a cephalon so I knew my luck was changing. It turned out to be a mini mother-lode of cephalons but no full trilobites, which apparently are very rare. While we found a few cephalons among the loose pieces of shale, I had much better success digging out larger slabs and splitting them. I haven’t yet gone through them in detail to make good identifications but they look primarily like Olenellus species, which are what you will predominantly find. Some sample photos below. Given that I didn’t have to pay to dig and it took considerable effort to find anything, I have to say this was the more enjoyable day of digging. But if you go, be aware that many people who go there don’t find anything. The day we were there I only saw one other person. (He tagged along with my success to dig nearby.) On the way home, we took Nevada Highway 375, known as “The Extraterrestrial Highway” because it runs close to the infamous Area 51. We stopped in the tiny hamlet of Rachel to visit the Little A’le’Inn, a souvenir shop, diner, and motel. If you get the chance, be sure to stop in. On my last U-Dig adventure I spent a night there, which was quite an experience (you can read about it here). I don’t think it has changed much in the last 8 years except there were more tourists there this time. Overall, we had a great time. Once I sort through everything I will post a few samples for help with identification. The sign along US Highway 6: U-Dig office: Steve digging (friendly dogs belong to another digger): The haul back at home: Elrathia kingii (I think it's a molt): Small Elrathia kingii: Peronopsis (needs more prep):

My wife and I are starting to plan a trip for late September from our home in Northern California to do some trilobite hunting in Nevada and Utah. Our main objective will be the U-Dig quarry out of Delta, Utah, but I'm also thinking of stopping at the Oak Springs Trilobite Site near Caliente, Nevada. I've been to both places once before, about 10 years ago. I did pretty well at U-Dig but struck out at Oak Springs because I didn't know what I was looking for. Does anybody have any current advice for either of these sites? I tried to search this forum for "U-Dig" but it returned no results even though I know some of you have posted about your trips there in the past. And if anybody has any advice for Oak Springs (necessary tools, how to search, etc.), I'd appreciate it. And if there are any other sites we should visit along the way (we won't be able to get to Green River this trip), let me know. I'll update my post once we get back (assuming we don't strike out!).