110 STALK- AND SESSILE-EYED CRUSTACEA 
Antenne inserted upon, not beneath the front margin of the head. 
Epimere not visible. Legs all adapted for walking, rarely with the two 
first pairs terminating in a strong curved claw. Inner ramus of the 
caudal appendages immobile, or sometimes obsolete. Branchie ciliated. 
Maxillipeds elongated, 5-6 jointed, and usually palpiform. 
Sub-Family I. SpHarromina. 
Spheromine, Dana, U.S, Explor, Exped. xiv, Crust. part 1, p. 748» 
(1853). 
Legs all adapted for walking. External ramus of the caudal appen- 
dages capable of being folded beneath the inner ramus. 
_SPHAEROMA. 
Sphaeroma, Latr. (part) Hist. Nat. Crust. vu, p. 11, (1804); M. 
Edw. Hist. Nat. Crust. in, p. 202, (1840); Dana, U.S. Explor. Exped. 
xiv, Crust. part 11, p. 748, (1853). 
Oblong-oval, convex. Head broad. Eyes small, circular, received 
in an emargination of the first segment of the body. First segment 
of the body the largest, the rest subequal, marked on. the sides with 
an oblique line indicating the coxe, seventh segment without a dorsal 
spine. Terminal segment of the abdomen large, convex, rounded and 
entire at its extremity. Antenne separated at base by a small frontal 
process, the inner very broad at the base, the outer longer. Rami of 
the caudal appendages oval, lamellate, subequal. 
So far as I can ascertain, no remarkable sexual differences exist in 
this genus, such as are found in Zuzara and other genera. 
117. Sphaeroma gigas. 
Sphaeroma gigas, Leach, Dict. Sci. Nat. xii, p. 346, (1818); M. 
Edw. Hist. Nat. Crust. ii, p. 205, (1840). 
Broad oblong-oval, slightly and regularly convex, nearly smooth. 
Head small, transverse-oblong, anterior margin with a very small lobe 
between the enlarged bases of the superior antenne. First segment 
of the body rather the longest, the rest short, subequal, slightly 
tending backward on the sides, and with the infero-posterior angle 
subacute. Inferior lateral margins of all the segments grooved. 
Abdomen two-jointed, the terminal jomt large, convex, smooth, sub- 
