78 A HISTORY OF RECENT CRUSIACEA 
CHAPTER VII 
TRIBE II.—CATOMETOPA 
Tue ‘front’ 1s bent downward. The carapace is broad 
anteriorly, often subquadrate, sometimes subglobose, trun- 
cate or arcuate forwards, but not rostrate. The epistome 
is short, often almost linear. The pairs of branchiz are 
usually fewer than nine in number; the efferent channels 
open at the sides of the endostome. The third maxilli- 
peds have the fifth jomt articulated at the front outer 
angle of the fourth, or less frequently at its apex, or very 
rarely at the front inner angle. The male verges are 
inserted either in the sternal plastron, or in the basal 
joints of the last pair of legs, thence passing through 
channels in the sternum beneath the pleon. 
The tribe contains four families, the Gecarcinide, 
Ocypodidae, Grapside, and Pinnotheride. The liver is 
said by Milne-Edwards to be in general central, extend- 
ing little or not at all over the branchial cavities. 
Family 1.—Gecarcinide. 
The carapace is dorsally very convex, especially dilated 
over and in front of the branchial regions, with the antero- 
lateral margins usually entire and strongly arcuate. The 
‘front’ is of moderate width and strongly deflexed. The 
orbits and eye-stalks are of moderate size. The third 
maxillipeds have the fifth joint articulated at the front 
outer or near the front inner angle or at the apex of the 
fourth, which sometimes completely conceals it. The 
chelipeds in the adult male are powerful, usually unequal. 
The seventh joint in the walking legs is nearly always 
