722 



BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



dinate groups, herein discussed. It is, therefore, by no means a sum- 

 mary of the invertebrate fauna of the Laramie period. 



Table shotcing the GeograpMcal Distribution of Species in the Laramie Chroup. 



Oatrea ■wyomingensis Moek 



Anomia micionema Meek 



Anotnia gryphorhynchus Meok 



Brachydontes regularis White 



Unio oryptorhynchus White 



■Corbicula (Leptesthes) fracta Meek 



Corbicula (Leptesthes) subelliptica Meek 



Coi'bicula (Veloritina) cythoiiformis M. & H 

 Corbicula (Veloritina) occideutalis M. & H ... 



Corbula perundata M. & H 



Corbiila undifera M. & H 



Bulinus longiusculus M. & H 



Bnlinus subelongatus M. & H , 



Colmnna teres M. & H 



Macrocyclis spatiosa M. & H 



Goniobasis teDuicarinata M. & H 



•Goniobasis graoilienta M. & H 



Melauia wyomingensis Meek 



'Campeloma vetula M. & H 



Campeloma multiliueata M. & H 



Tulotoma thompsoui White 



The underscoie of the asterisk in the above table indicates the region in which the species thus 

 (lesignated was originally discovered. The double vertical line may be taken to represent the Eocky 

 Mountains, or the great range, extending northward through Colorado, Wyoming, and Montana ; the 

 localities named on its left being east, and those on the right, west of those mountains. 



Ttie region indicated in the table as " South Platte Valley" embraces 

 quite a large area east of the Eocky Mountains in Colorado, which is 

 drained by the South Platte and its tributaries, and extends eastward 

 from the base of the mountains out upon the x)lains, a known distance 

 of 150 miles, and doubtless much further. 



The Bitter Creek series, as here indicated, embraces all the strata that 

 were included by Mr. Meek under the same designation in Hayden's 

 Sixth Annual Eeport of the Geological and Geographical Survey of the 

 Territories. Those of the well-known localities, Kock Springs and Black 

 Buttes Stations, are both included in this series, and not regarded as 

 separate, as they were in one of my former i^ublications (Geology of the 

 Uinta Mountains, Chapter III). The Yampaand White River Valleys are 

 adjacent regions west of the Eocky Mountains, in Northwestern Colorado. 



The strata here included under the head of " Bear Eiver Valley" are 



