286 HGIDA. 
ISOPODA. AGID A. 
NORMALIA. 

AGA MONOPHTHALMA. 
Specific character. Oval, convex, eyes very large, uniting dorsally, ex- 
tending obliquely backwards, the anterior margin of the first segment of the 
pereion being deeply incised on each side for their reception, terminal segment 
of the pleon flat, nearly semicircular, with a central carina terminating in a 
point. 
Length, 2} inches. 
Adiga monophthalma. Jounston, in Loudon’s Mag. Nat. Hist. vii. 
p. 233, £. 43. 
Rocinela monophthalma. Mine Epwarps, Crust. iii. p. 244. Wuire, 
B. M. Cat. Brit. Crust. p. 80. Pop. Hist. 
Brit. Crust. p. 252, pl. xiv. f. 7. Gossz, Man. 
Mar. Zool. 1, fig. 233. 
THE animal is oval, of a pale brown colour, approach- 
ing to fleshy red, and when alive tinged with purple, 
dotted all over with numerous punctures. The upper 
antennz are very short, the two basal joints much 
dilated, forming together a broad movable plate; the 
flagellum is setaceous, the lower antennz more than twice 
the length of the superior, the three basal joints short 
and unequal, the flagellum multiarticulate. The head is 
almost entirely occupied by the large oblong eyes, which 
