120 Bulletin American Museum of Natural History. [Vol. XXXIV. 
I examined a P. bridgerensis (9001, near Fort Bridger) in the U. S. 
National Museum. It has a form rather suggestive of the P. acuta group; 
length 38 mm.; quite distinct from P. pleromatis by the long spire; vertical 
growth striz fine, not inclining to large flat bands as in pleromatis; a heavy 
callus on inner side of aperture. 
Campeloma calamodontis n. sp. 
Shell about 33 mm. long and 23 broad; whorls about five, strongly shouldered, 
the suture deep, outer face of whorls enti dale flattened; lip (as shown by lines of 
hd growth) not aecodly sinuous; shell rather 
thin, smooth, without evident sculpture; 
no trace of spiral lines or ridges. 
In purple-stained rock, Wasatch (Eo- 
cene), at Ojo San José, New Mexico 
(Stein, July 16, 1912). Several specimens. 
This has all the appearance of a 
Campeloma, rather closely resembling 
the modern C. ponderosum Say, but 
apparently thinner, with much more 
Fig. 5. Campeloma calamodontis n. sp. flattened whorls. 
It resembles C. multilineatum (Meek 
& Hayden), but the heel are more broadly shouldered, and although the 
surface is well preserved, there are no spiral lmes. The lip is straighter 
than in some of the species (e. g. C. macrospira Meek), but not more so 
than may be seen in living shells. In one specimen the whorls appear not 
to be shouldered, but this is due to compression and fracture. 
There is a curious resemblance to White’s figure of an internal cast of 
Viiparus panguitchensis White, but our shell shows the surface, without the 
sculpture or subbasal angulation of that species. 
