CHAP. IX. ] THE DEEP-SEA FAUNA. 465 
Mexico. The abyssal mollusca are by no means de- 
void of colour, though, as a rule, they are paler than 
those from shallow water. Daecrydium vitreum— 
a curious little mytiloid shell-fish which makes and 
inhabits a delicate flask-shaped tube of foraminifera, 
Fic. 78.—Pleuronectia lucida, JEFFREYS. Twice the natural size. a, from the Eastern Atlantic 
b, from the Gulf of Mexico. 
sponge spicules, coccoliths, and other foreign bodies, 
cemented together by organic matter and lined by a 
delicate membrane—is of a fine reddish brown colour 
dashed with green, from 2,435 fathoms; and the 
Fie. 79.—Pecten hoskynsi, FoRBes. Twice the natural size. 
ynst, 
animals of one or two species of Zima from extreme 
depths are of the usual vivid orange scarlet.. Neither 
are the abyssal mollusca universally destitute of eyes. 
A new species of Plewroloma from 2,090 fathoms had 
a pair of well-developed eyes on short footstalks; and 
tie 
