MEGAMCERA BREVICAUDATA. 
409 
A M PIT IP ODA . 
NAT ATOM A. 
OA MM A RIDES. 
MEGAMCERA BREVICAUDATA. 
Specific character. Posterior margin of the first three segments of the 
tail slightly serrated. Superior antennae having the flagellum short. Second 
pair of gnathopoda larger than the first. Propoda long-ovate. Posterior pair 
of pleopoda with the rami short. 
Length 5 6 0 inch. 
Gammarus brevicaudatus. Spence Bate, Rep. Brit. Assoc. 1855, p. 58. 
Ann. Nat. Hist. 2 ser. xix. p. 145. White, 
Pop. Hist. Brit. Crust, p. 185 (not of Milne 
Edwards). 
Megamcera brevicaudata. Spence Bate, Cat. Amph. Brit. Mus. p. 228, 
pi. xl. fig. 2. 
This species was first mistaken, by Mr. Spence Bate, 
for Gammarus brevicaudatus of Edwards, with the de- 
scription of which it was supposed to correspond. The 
opportunity since afforded to us of examining the typical 
specimen preserved in the Museum of the Jardin des 
Plantes, having demonstrated that the Parisian specimen 
belongs to another genus, we have retained the specific 
name for the present animal. 
The body is robust, with the hinder portion compara- 
tively short. The three anterior segments of the tail 
have the posterior margin slightly serrated. The su- 
