176 
The chief differences appear to he, that the present species has 
ino-re general convexity and the spire itself is slightly convex : 
beneath, the breadth is less considerable between the outer mar- 
gin and the edge of the mouth, and the revolutions of the spire 
within are much more obvious. PL 25, upper and lower figures. 
SiGARETUS MACULATES. — Specific character. Shell with two 
maculated bands. 
Desc. Shell oval, depressed, with very numerous, transverse, 
hardly undulated, subequidistant, impressed lines, and longitudinal 
wrinkles ; the transverse lines are obsolete beneath ; two bands of 
pale rufous spots, and a rufous band near the suture : spire hardly 
prominent, slightly convex ; volutions about three ; suture a simple 
impressed line : aperture very large. 
Ohs. Although very much depressed, this pretty species is more 
convex than the preceding, and the spire when viewed from the 
side is more distinct ; the strim also are more close set. It differs 
from all the species in having colored spotted bands, and within it 
has a slight pearly appearance. This species is found on the 
southern coast and is rare. PI. 25, middle figures. 
Venus. — Shell equivalved, inequilateral, regular, closed, trans- 
verse or suborbicular ; cardinal teeth three on each valve, approxi- 
mate, anterior and posterior ones diverging from the summit; liga- 
ment exterior; muscular impressions two, not elongated, remote, 
eonnected by the submarginal impression, which is deeply sinuous 
before. 
Ohs. In this extensive genus are included some of the most 
beautiful of bivalve shells. Linnd referred to it species of the fol- 
lowing genera : Petricolay Venerupisj Sanguinolaria, Corhis^ 
Lucinaj Donax, Astarte, Gyrena^ Cyprina, Megadesma^ Cytherea^ 
Verms and Venericardia. Although those species have been 
since eliminated and more naturally distributed, yet in consequence 
of the great accessions from the zeal of modern observers, and 
owing to the considerable variation, both in sculpture and coloring, 
that many of them undergo, great difficulty and uncertainty often 
meet the conchologist in his endeavors to ascertain species, and 
more than usual caution is requisite in detemining any one to be 
new. 
In general form and exterior appearance these shells are undis- 
tinguishable from Cytherea^ but the hinge of the latter has the 
