A MATH ILIA. 
859 
AMPHIPODA. 
NATATORIA. 
GA MM A RI DES. 
Genus— AMATH ILL A. 
Amathia * Rathke, Fauna der Krym. Spence Bate, Rep. Brit. Assoc. 
1855, p. 58. Ann. Nat. Hist. 2 ser. xix. p. 143. Cat. 
Amph. Brit. Mus. p. 197- White, Pop. Hist. Brit. Crust. 
p. 182. 
Generic character. Head produced to a short sharp point 
between the antennae. Antennae rather short, subequal in 
length, the upper appendiculated. Gnathopoda with small 
subequal propoda. Body and tail carinated ; and destitute 
of spines. Telson entire, slightly emarginate at the tip. 
Three posterior pairs of pleopoda sub-equal, one of each pair 
of rami slightly smaller than the other, those of the last pair 
more foliaceous and equal. 
In all the species of this genus the back is elevated 
into a carina, which is most strongly developed along the 
caudal segments. The eyes are normal. The antennae 
subequal ; the superior pair being furnished with a 
secondary appendage about one-third of the length of 
the flagellum, and composed of four oblong articuli, 
whereas the articuli of the flagellum of all the an- 
tennae are extremely short. The first two pairs of 
legs are small, subequal, uniform, and subchelate. The 
walking legs are subequal. The last pair of the caudal 
appendages terminate in two branches of equal length, 
and do not extend beyond the branches of the preceding 
appendages. The central tail-piece is single. 
* The name Amathia having "been long ago proposed by Lamarck for a genus 
of Polyps, by Pol. Roux for a genus of Decapod Crabs, and by Duponchel for 
a genus of Moths, we have, to avoid confusion, slightly altered the name. 
