A Little extra Baggage

[FossilDAWG]

I collected both Glyptocystites and Homocystites in Ottawa, but I can't say much about the relative abundance. When I lived there, there weren't any active quarries in the Bobcaygeon (=Hull in the older terminology) or Verulam (=Sherman Falls) formations. The old Hull quarries were filled with water, exposed only vertical faces, and were fenced off anyway. My collecting was mostly done from natural exposures along the Ottawa River, and from one particular roadcut in the Lindsey (=Cobourg) that was quite productive at that time, although even then it's most productive days were over. So I had no access to fresh blast piles, the closest I could get was an occasional construction site that exposed Billings or Carlesbad shales, good for trilobites but not echinoderms. If I was very lucky, I would find a productive spot and get a few decent specimens, but invariably I was limited in how far I could excavate into nearly vertical exposures, and I had to depend on natural rates of erosion to expose new rock. So all in all I think I was lucky to find the diversity of species I did, but I certainly don't have enough of a sample to say what is rare and what is common for most species. I think I can say that Pleurocyctites is the most common cystid, though, as I collected it at almost every site that yielded echinoderms at all. After I left Ottawa, the city went through a lot of road construction that exposed new outcrops and also required opening new quarries, so I understand the opportunities for collecting were significantly improved, at least for a time.

Don

[Carl]

Two nutso echinoderms for the price of one! Lucky DOG!

[Ludwigia]

I'm on holiday right now, so I don't have much access to PCs. Just got a chance and popped in for a quick look. Great find, Malcolm! Congratulations!