144 
GAMMARID2E. 
second and third joints are small; the flagellum consists 
of seven articuli, and is rather longer than the peduncle. 
The secondary appendage is about half the length of the 
primary. The inferior antennm are slightly longer than 
the superior ; the peduncle extends beyond the peduncle 
of the superior ; the flagellum has the first four or five 
articuli very short, the remainder irregularly increasing 
in length. The foot-jaws nearly resemble true legs, and 
terminate in a short sharp-pointed finger, retaining the 
characteristic of their true nature only in two small scale- 
like processes, springing from the second and third joints, 
— the joints are all of the same length. The large squa- 
mose coxae of the four anterior pairs of legs are deeper 
than their respective segments, the three anterior having 
the posterior half of the inferior margin furnished with 
five hairs, the hindmost of which is short. The coxae of 
the three posterior pairs of legs are much shorter than 
those of the preceding pairs. The first two pairs of 
legs are subequal, tolerably strong, each having a hand 
of nearly similar form ; that of the first pair is almost 
quadrate, the margins nearly parallel, the palm is some- 
what oblique, slightly convex, and slightly serrated, de- 
fined by a short sharp tooth. Those of the second pair 
are rather longer, and have the palm defined by a longer 
and sharper denticle ; the fingers are sharp and slightly 
curved. The next two pairs of legs are slender ; the 
fifth pair are tolerably robust, but not very long, having 
the second joint considerably dilated posteriorly ; the 
sixth pair are longer than the fifth, very similar in form. 
The seventh also resemble them, but are very much 
shorter, the third and following joints being scarcely as 
long as the largely-dilated second joint ; all the legs after 
the first two have the finger very short. The three pairs 
of natatory appendages are not very long, and are pro- 
