PLANOBBIS. 199 
13. PLANORBIS BINNEYI, 7Zryon. 
Hald. Monog. p. 19, pl. 3, figs. 7—9. 
This is the Planorbis corpulentus of Halde- 
man in part, but it is not the species published 
under that name by Mr. Say, which I agree 
with Mr. Binney in considering nothing but a 
fully-developed form of Pl. trivolvis: Mr 
Binney’s figure 193, however, is a young PI. 
ammon. 
Pl. Binneyi is abundant in various localities 
in Washington Territory and Oregon. 
14. PLANORBIS TENUIS, Phalippt. 
Plate 6, fig. 7, 8, 9. 
Shell large, very thin, shining, very deli- 
cately striate, pale horn or smoke-colored ; 
concave on each side, umbilicated above, 
deeply excavated below; whorls swollen, 
rounded, above narrow, subcarinated below 
and rapidly increasing; aperture sinuous, sub- 
auriculate. 
(46) 
