MONTANA FAUNA OF LARAMIE PLAINS. 



139 



Ostrea inornata, M. and H. 

 Ostrea plumosa, Morton. 

 Syncylonema rigida, (EL and M.) 

 Avicula Ungueeformis, E. and S. 

 Inoceramus cripsii, var. bambini, Morton. 

 Inoceramus sagensis, Owen. 

 Inoceramus sagensis, Owen, variety. 

 Inoceramus, n. sp. 

 Modiola meeki, (E. and S.) 

 Pinna lakesi, White. 

 Limopsis parvula, M. and H. 

 Eriphyla gregaria, M. and H. 

 Liopistha (Cymella) undata, M. and H. 

 Dental ium gracile, H. and M. 

 Margarita nebrascensis, M. and H. 

 Lunatia occidentalis, M. and H. 

 Anchwa rostrata, (Gabb.) 



Cerithiopsis moreauensis, M. and H. 

 Fasciolaria (Piestochilus) alleni, "White. 

 Fusus (Serrifusus) dakotensis, M. and H. 



var. 

 Baculites ovatus, Say. 

 Placenticeras placenta., (Dekay.) 

 Placenticeras placenta, var. intercalare, M. 



and H. 

 Ptychoceras mortoni, M. and H. (?) 

 Ptychoceras crass am, Whitfield. 

 Heteroceras angulatum, M. and H. (?) 

 Heteroceras nebrascense, M. and H. 

 Heteroceras eochleatum, M. and H. 

 Emperoceras beecheri, Hyatt (?) 

 Helicoceras mortoni, var. tenvicostatum, M. 



and H. 

 Scaphites nodosus, var. brevis, Meek. 



The other fossil if erous horizon which is 300 or 400 feet lower, yields 

 many of the same species, together with a few others that seem to be 

 peculiar to it, as will be seen by the following list : 



Ostreq pellucida. M. and H. 



Ostrea inornata, M. and H. 



Anomia sp. 



Syncyclonema rigida, (H. and M.) 



Camptonectes cf. parvus, Whitfield. 



Avicula lingueeformis, E. and S. 



Avicula nebrascana, E. and S. 



Gervillia sp. 



Inoceramus cripsii, var. barabini, Morton. 



Inoceramus sagensis, var. nebrascensis, 



Owen. 

 Inoceramus pertenuis, M. and H. 

 Modiola alternata, M. and H. 

 Pinna lakesi, White. 

 Yoldia evansana, M. and H. 

 Trigonia, n. sp. 



Caprinella coralloidea, H. and M. 

 Protocardia subquadrata, (E. and S.) 

 Cardium speciosum, M. and H. 

 Legumen planulatum, Conrad. 

 Tellina scitula, M. and H. 

 Glycimeris berthoudi, White. 

 Anatina sp. 

 Liopistha (Cymella) undata, M. and H. 



Mactra sp. 



Dentalium gracile, H. and M. 



Lunatia occidentalis, M. and H. 



Vanikoro ambigua, M. and H. 



Margarita nebrascensis, M. and H. 



Anchura americana, (E. and S.) 



Anchura rostrata, (Gabb.) 



Aporrhais meeki, Whitf. (?) 



Fusus (Serrifusus) dakotensis, M. and H. 



Pyrifusus newberryi, M. and H. (?) 



Fasciolaria (Mesorhytis) gracilenta, M. and 



H. (?) 

 Anisomyon borealis, M. and H. 

 Anisomyon patelliformis, M. and H. 

 Cylichna sp. 

 Actseon sp. 



Pachydiscus complexus, (H. and M.) 

 Placenticeras placenta, var. intercalare, M. 



and H. 

 Baculites ovatus, Say. 

 Ptychoceras crassum, Whitf. 

 Heteroceras sp. 

 Helicoceras mortoni, var. tenuicostatum, M. 



and H. 



The species of these lists are nearly all of common occurrence in the 



