FOSSILS FROM THE CRETACEOUS FORMATIONS 591 



In commenting on the age of these fossils, Doctor Knowlton says of 

 the plants : 



"Notwithstanding the fact that this collection is from rocks generally re- 

 garded as of Laramie age, there is not a single species in it that suggests the 

 Laramie (of the Denver Basin). It is the same flora as that at Point of 

 Rocks, Wyoming, and so far as I can see is of the same age, namely, Montana." 



The shells collected by the ^vriter are beautifully preserved, but they 

 are of fresh-water species. Doctor Stanton says of them: 



"I consider tliis a Laramie fauna. The unios are Lance types and the gas- 

 tropods are of types tliat range from Mesaverde to Lance." 



In addition to the fossils named above, a number of invertebrates have 

 been collected from the ^'Laramie" of southwest Colorado by Kobert For- 

 rester (113, page 274) and J. A. Taff. Their collections have been 

 joined with those made by the writer and by Doctor Gardner to make 

 the following list, which includes all of the invertebrates known from 

 the "Laramie" of southwest Colorado. The marine forms come from the 

 Pictured Cliffs sandstone and the brackish water forms from the lower 

 part of the shaly portion of the "Laramie" formation, although many 

 of the latter occur above the principal coal bed. The fresh-water forms 

 are from higher horizons : 



Fossil Invcrtehj'ates of the ''Laramie'' Formation of soiithicest Colorado 



Anomia sp. related to JL. micronciita Martcsiaf sp. 



Meek Mckinia icyomingensis Meek? 



Anomia sp. " sp. 



Campeloma? sp. UodioUi laticostata White 



Cardium speciosum M. & H. Neritina sp. 



CorMcula sp. related to C. subelliptica Ostrea sp. 



M. & H. Pliosas? sp. 



CorMcula occidentalis M. & H. Sphwrium sp. 



" sp. Tcllina scitula M. & H. 



Coi'bula undifera Meek Tulotoma tliompsoni White 



" sut)trigonalis M. & H. IJnio holmesianus White 

 " sp. " t)rachyopisthus White 



Cypris? sp. " verrucosiformis Whitfield? 



Goniohasis? sp. " sp. related to U. aldrichi White 



Inoceramus haraMni Morton " sp. undescribed, possibly 2 species 



Inoceramns sp. Viviparus sp. 



The relation of the so-called Laramie to the younger formations ex- 

 posed along the Animas River is not yet satisfactorily determined. Sev- 

 eral hundred feet above the horizon of the fossils collected by the present 

 writer there is a distinct change in lithology. A hard, massive, cliff- 



