EEPOET OUST THE BEACHYUEA. 
109 
B. The endostome or palate with distinct longitudinal ridges defining the apertures 
of the efferent branchial channels (family Eriphiidse, Dana ; pt.). 
a. The antennse not excluded from the orbit : — 
Eurytium, Stimpson. Sphaerozius, Stimpson. 
Pseudozius , Dana (subgenus Eury- Pilumnus, Leach. 
ozius, m). 
b. The antennse excluded from the orbit, whose interior hiatus is closed : — 
Eriphici, Latrielle. 
A. Endostome not longitudinally ridged (Cancridse, Dana) : — 
Cancer , Lamarck. 
Cancer, Lamarck, Syst. Anim. sans Vert., p. 148, 1801. 
„ Leach, Trans. Linn. Soc. Lond., vol. xi. p. 320, 1815. 
„ A. Milne Edwards, Nouv. Archiv. Mus. Hist. Hat., vol. i. p. 185, 1865. 
The carapace is depressed or moderately convex, very widely transverse or elliptical ; 
its dorsal surface is smooth or uneven, with the regions very obscurely defined ; its 
antero-lateral margins are regularly arcuated and are divided into ten lobes or teeth, 
which are sometimes broad, subtruncated, and little prominent, sometimes more prolonged 
and acute, and which may themselves be armed with accessory denticles ; the postero- 
lateral margins are shorter than the antero-lateral margins, and defined by a raised line 
or crest (the postbran chial crest). The front is relatively narrow, and is divided into 
five lobes or teeth (if the lobes which constitute the superior and interior orbital angle 
be included) and projects somewhat beyond the orbits, which are small and sometimes 
dentated ; the teeth defined by two fissures in the superior and two in the inferior 
margins. The post-abdomen in the male is five-jointed, with the third to the fifth joints 
coalescent. The eyes are small and are set on very short thick pedicels. The antennules 
are longitudinally or nearly longitudinally plicated. The basal antennal joint is somewhat 
enlarged with a distal lobe or tooth, which unites with the front so as to exclude the 
short flagellum from the orbit. The exterior maxillipedes have the merus-joints usually 
distally truncated, with the antero-external angle not produced, and they are usually 
more or less distinctly notched on the inner margin, but the notch is sometimes obsolete. 
The chelipedes are usually subequal and not very largely developed, and their palms are 
nearly always longitudinally costated on the exterior surface ; fingers acute and dentated 
on the inner margins. The ambulatory legs are somewhat elongated, with the dactyli 
slender and nearly straight (not Batedand flattened as in Metacar cinus). 
