THE MOLLUSCA OF COLORADO 57 



Genus PUPOLDES Pfeiffer 

 Pupoides hordaceus Gabb. 



I collected one specimen at Bellevue, Larimer County. 



Genus PUPILLA Leach 

 Pupilla muscorum Linn. (var.). 



Tolland (Cockerell, Nautilus, Vol. XX, p. 59); Eldora (Henderson). We have a 

 small form of this species from Floyd Hill, Clear Creek County (Hand), Magnolia (D. M. 

 Andrews), Eldora Lake (Bethel), and Mr. E. G. Vanatta, who has seen a portion of our 

 specimens, says the same form is in the Academy of Natural Sciences of Philadelphia, 

 from Trinidad (Pilsbry), Estes Park (Ashmun) and Black Lake Creek (Cockerell). The 

 shells from these localities are uniformly smaller than typical muscorum and not so acute 

 as minor from Transylvania. It is perhaps entitled to a separate name as a variety of 

 muscorum. 



Pupilla blandi Morse. 



Five miles above Gleneyrie, Jackson County (Fleming); Copeland Park, Boulder 

 County (S. A. Rohwer); Ward, Tolland and Sulphur Springs (Dodds); Pike's Peak at 

 8,900 feet, and Swift Creek, Custer County (Cockerell); Denver (Bethel); near Ohio 

 City (F. Rohwer); Calypso Falls, west of Allen's Park, Boulder County (Spangler). I 

 have found it at Axial (Routt County), Owl Canyon (Larimer County), Morrison, 

 mouth of Little Thompson Canyon northeast of Lyons, at Rio Blanco, Buford, above 

 Meeker, Marvine Lodge and Mud Spring (Rio Blanco County), at various places in the 

 southwest corner of North Park and other localities. It appears to be the most abundant 

 and most generally distributed of the Colorado Pupillidae. 



Pupilla syngenes dextroversa Pilsbry and Vanatta. 



Professor Cockerell collected one at Tolland (Nautilus, Vol. XX, p. 59), and I 

 obtained another at Eldora. 



Genus BLFIDARIA Sterki 

 Bifidaria agna Pilsbry and Vanatta. 



Type locality Trinidad (Nautilus, Vol. XX, pp. 140-141, 1907). 



Genus VERTIGO Draparnaud 

 Vertigo cone inn ul a Cockerell. 



Professor T. D. A. Cockerell has recently examined all the Colorado Vertigos in the 

 University cabinets and the records of concinnula and basidens included herein are based 

 upon his identifications. Allen's Park (Spangler), Floyd Hill (Hand); Boulder (Bethel); 

 Ward (Dodds); Tolland (Betts); Pike's Peak, 8,900 feet (Cockerell); Eldora, Marvine 

 Lakes in Rio Blanco County and southwest comer of North Park (Henderson). 



A comparison of the records of this species with the next indicates that concinnula 

 is the common one east of the Continental Divide, while basidens is the common one west 

 of the Divide. V. concinnula is quite variable and possibly should be divided into two 

 or three varieties or races. One of these, from Tolland, has been recorded as V. modesta 

 parietallis Ancey (Cockerell, Nautilus, Vol. XXV, p. 59), with the statement that it is 

 not quite typical parietalis, belonging rather to the form which Ancey named ingersolli. 



