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Hello everybody, I am starting this topic as I need some help with identification of some Trigonostoma type fossils I found at Whiskey Bridge. I think they may be my favorite type of gastropods I found there. There are 3 types listed in Emerson book but I think I have more than that. The picture here shows 7 specimens (5 & 6 are the same, one and I will start from the left in this discussion. 1. this one looks very similar to T. penrosei but the main difference is that the shoulders are rounded, not flat topped like a normal Trigonostoma. The ribs are more prominent and spaced further apart. The aperture is a different shape and it has 3 folds on the columella instead of 2 like T. penrosei. The line and spiral ornamentation is basically the same and the umbilicus is covered up by the callus. 2. also looks similar to T. penrosei (and somewhat similar to a Bonellitia parilis but I ruled out B. parilis due to the ornamentation being different, aperture has a flat outline on top and has 3 distinct folds on the columella) but is shorter and more squat. It has periodic large ribs showing where the aperture was located at. It has a fairly flat topped shoulder and the ornamentation is more pronounced. It has 3 folds on the columella. 3. Trigonostoma panones juniperum 4. Trigonostoma penrosei 5 & 6. unknown type that is more of a T. babylonicum style but has a more pronounced rib structure, that are straight and do not have a slant to the left as the other Trigonostoma types do. 5 is a more juvenile specimen than 6 as the ribs disappear and the only ornamention left is prior aperture locations on the more adult one. 6 has serial dentation on the out lip and 5 does not. 7. Trigonostoma babylonicum. If anybody has any ideas please let me know. Or if better pictures are needed I will try my best at that. Thanks, Stephen