LYMNEIDA OF NORTH AMERICA. 153 
is the most elongate race of stagnalis in America and were it not for 
certain intermediate examples might easily rank as a species. 
Westerlund’s subulata (Expose. Crit., 1871) is similar to wasat- 
chensis, but has 8-9 whorls and the aperture is more oblong. In the 
Smithsonian collection there is a peculiar form from near Fort Col- 
ville, Washington (No. 9322) which may be regarded as an extreme 
form of wasatchensis. The spire whorls are long and tapering, but 
the body whorl suddenly expands to about double the diameter of the 
penultimate whorl and is notably flat sided near the suture. A char- 





acteristic specimen measures: Height, 42.00; breadth, 18.50; aper- 
ture height, 19.50; breadth, 10.50 mill. The breadth of the last whorl 
is 18.50 mill. while that of the preceding is but 9.00 mill. The speci- 
mens from Fort Anderson, though far removed from the original 
locality, seem to be good examples of the race. 
Lymneza stagnalis lilliane (Baker). Plate XXI, figures 8-12; 
plate XXII, figure 6. 
