114 MOLLUSCA. 
pl. 15. fig. 9. Hatpreman, Monograph of Limniades (Planorhis), pl. 
3, fig. 7-9. 
Animat dark emerald green, profusely dotted above and below with 
small white points, paler beneath. Head large, tentacles very slender. 
Inhabits the Columbia River, Oregon. Drayton. 
Figure 130, side view of the shell and animal; 1304, the locomo- 
tive disc of the animal; 1300, the head in outline. 
* 
PLANORBIS KERMATOIDES (D’Orpicny), Amerique Merid., 350, pl. 
45, fig. 1-4. 
Anima dusky olive green; beneath, paler at the centre and edges of 
the foot ; head broad and pale. 
Inhabits streams near Lima, Peru. Couwthouy. 
PLANORBIS FERRUGINEUS (Srix), Test. Brazil., pl. 18, f.1,2. D’Or- 
BiGNY; Amer. Merid. 
The animal of this species is remarkable for the great length of its 
slender tentacles, and for the beauty of its coloration. Mr. Couthouy 
describes it as varying from a deep orange red to a bright, transparent 
cherry colour. A variety was found with the animal ashy-brown ; 
and he figures a variety with both shell and animal of a deep bottle- 
green, though with some doubt as to its being the same species, as it 
seems to have fewer whorls and a coarser surface. 
Mr. Couthouy remarks, that he was surprised to find how barren of 
mollusks all the fresh waters in this region are; for, though as many 
as forty different streams were explored, this shell, with a single Ain- 
pullaria and a single Melania were the only species detected. 
PLANORBIS TRIVOLVIS (Say); Nicholson’s Encye. iv., pl. 2, f. 2. 
Amer. Conch., pl. 54, f. 2. Hatpeman; Limniades, pl. 2, figs. 4-7, 
GotvLp; Inverteb. of Mass., 201, fig. 131. 
