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ORCHESTIlDiE. 
AMP HIP OR A. ORCHESTIIDJZ* 
SALT ATOM A. 
Genus— ORCHESTIA, Leach. 
Talitrus (part), Latreille. 
Generic character . — General appearance of Talitrus, but having 
both pairs of gnathopoda subchelate. The second pair in the 
male large and powerful ; in the female small and feeble. 
Telson single and well developed. 
The superior antennae are as short as in Talitrus , and 
are often recurved. The inferior antennae, as in that 
genus, have the two basal articulations incorporated into 
the anterior or frontal wall of the head, and destitute 
of the olfactory denticle. The mandibles are without 
an appendage,* and the whole of the organs of the 
mouth are largely developed. The two anterior pair of 
legs are furnished with prehensile hands, the first pair 
small, the second large and powerful in the male, but 
small and feeble in the female. The squamiform basal 
joint of the fifth pair of legs is subequally bilobed, the 
anterior lobe being as deep as the scale of the preceding 
legs. The posterior pair of caudal stylets consist only 
of a single branch. The tail-piece is single and well 
developed, entire, triangular, with the margin spinous. 
This genus was founded by Leach to receive the Cancer 
( Gammarus ) littoreus of Montagu. That Dr. Leach was 
* A rudimentary palpiform appendage in an Egyptian species of Orchestia 
is represented by Savigny near the base of the jaw (copied in our figure, 
p. 27, fig. d), but we have never seen it in any speeies. 
