GAMMARIDiE, 
51 
ever, they are not soldered. The maxillipeds are un- 
guiculate. The four anterior pairs of coxae are largely 
developed. 
This family consists of several subfamilies, which 
differ from each other in more or less important points. 
The superior antennae are generally subequal to the 
inferior, and bear a secondary appendage at the base 
of the flagellum. This peculiarity, although occasion- 
ally absent in the adult state, is, we believe, invariably 
found in the young. One or both pairs of the fore-legs 
or arms have subchelate hands. # 
Sub-family.— STEGOCEPHALIDES. 
AntennsB more than one-fourth the length of the animal, sub- 
equal. Coxae of the second pair of gnathopoda, and of the first 
and second pairs of pereiopoda monstrously developed. 
In some genera the coxae of the first pair of legs are 
rudimentary, or, at least, not developed into scales ; 
whereas the second is always large, covering the pre- 
ceding when not squamiform. The hands are subchelate, 
and the caudal appendages are styliform. The middle 
piece of the tail is always single. 
This sub-family was established by Dana under the 
name of Stegocephalin^:, for the reception of Kroyer’s 
genus Stegocephalus. But there are several other genera 
which evidently fall within its definition. The principal 
feature, and one easily recognizable, is, the large size of 
coxae of the first two pairs of walking legs. These are 
so monstrously developed, that the animal has the power, 
when rolled up, of protecting, under this shield-like 
* By a subchelate hand is meant one in which the finger folds upon the 
hand, hut in which the inferior angle of the palm is not produced into an an- 
tagonistic thumb. 
E 2 
