Botany and Zoology. 133 
we 
Star rote paulo involute, ramis subradiatis, arcuiformibus, ramulis 
seriatis setiformibus. Segmentum caudale lamina caudali proxima 
paululo brevius.—Long. 2’. Rubra. | 
eyes are simple, and of extremely large size for the animals. ‘ he 
lens is a prolate spheroid, situated internally within the thorax, far re- 
mote from the cornea; the cornea is a broad oblate lens, perfectly 
pellucid and colorless, and connected with the exterior shell. e di- 
ameter of each of the latter in many Corycai is nearly balf the breadth of 
the thorax, and the two stand in the front like a pair of spectacles, huge 
for the minute animais so provided. in the same animal the prolate 
lens may be situated as far back nearly, as the middle of the thorax, 
so that a long space intervenes between it and the cornea. The ob- 
late form of the spectacle-like cornea, (we have called them in Lating 
conspicilla,) is fitted to compensate for the too great convexity or prolate 
ellipticity of the lens, and it serves the same purpose as glasses for a 
near-sighted person. f. 
he genus Sapphirina is closely related to Corycwus, and has the 
same peculiar eyes. ‘The only mention of these conspicilla, which has 
been made by any previous author, is to be found in a memoir i 
Meyenio in ista Expeditione collectorum; from the 16th vol. Nova Acta 
Ces. Leop. Car. Nat. Cur., page 156, pl. 27.—The species (probably 
a true Sapphirina) is called Carcinium opalinum. The conspicilla, by 
a mistake of observation (and it is not the only one in the description 
and much magnified figure ), are spoken of as dimples (Grubchen). They 
are not noticed by Thompson who established the genus Sapphirina. 
Similar eyes occur in some of the Caligus group, and the writer has 
established one genus, Specilligus, on this ground, which otherwise 
is identical with Nogagus. 
A cornea of lenticular form is by no means peculiar to these spe- 
cies of Crustacea ; but they have hitherto been observed only in com- 
pound eyes, in which case the lens and cornea are minute and not far 
distant 
4. Contributions to Conchology, Nos. 1-4: and Monograph of Sro- 
ASTOMA, a new genus of new operculated land shells, by Prof. C. B. 
*See last volume, p. 280; also, Proceedings of the Acad. Nat. Sci, Philadelphia, 
1845, ii, 235. 
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