ORDER DECAPODA — PORCELLANA. 21 
Genus Porcettana, Lamarck. Body suborbicular or subquadrate. External antenne very long, 
setaceous, placed behind the eyes; the internal concealed in cavities. Anterior feet very large ; 
the carpus very long, with a lamellar prolongation. Posterior pair small and slender, folded 
over the base of the others, and ending in a small didactyle pincer. Tail fan-shaped, bilamel- 
late on each side, 
P. pilosa. (Mitnr-Epwarps, loc. cit. Vol. 2, p. 255.) Shield elongated: front divided into three lobes, 
of which the central one is triangular and prominent, the others small and rounded; extremities 
very hairy. Carpus middle sized, and armed towards the base of its anterior edge with a denticu- 
lated lobe ; a few spines before this lobe. Hands short and wide; the following memters almost 
cylindrical. Color, brownish. Length, 0:5. Charleston, S. C. 
P. sociata. (Say, loc. cit. Vol. 1, p. 456.) Carpus and hand tuberculate before: tubercles very obtuse, 
each composed of from four to nine granules, Anterior part of the thorax deeply crenate ; crene 
inflected: in the two lateral ones are placed the eyes and antenne ; feet hairy. Length of thorax, 
0-2. Probably the same with the preceding. Coast of Georgia, 
P. galathina. (Bosc, Hist. Nat. des Crust. Vol. 1, p. 233, pl. 6, fig. 2. Say, Ac.Sc. Vol. 1, p. 458.) 
Shield flattened, striated longitudinally; pincers compressed; thighs dentate. This is all the infor- 
mation we have respecting this species. From an inspection of the figure, it appears to have the 
carpus strongly serrated, and the body and limbs punctate or tubercular; the Jength 0-4. Bose 
states its habitat to be unknown, and Mr. Say merely cites the name, and states it to be common on 
the coast of Georgia and Florida. Edwards does not cite it, but it may possibly be his P. pilosa.* 
Genus Monotepis, Say. Shield convex, oblong, with a small rostrum. Eyes very large and distant. 
Intermediate antenne stout, bifid at the end, and concealed under the rostrum. First pair of 
feet didactyle ; the three following monodactyle; the fifth very small, folded over the posterior 
part of the shield, and terminating in long sete. Tail ending in three plates. A double series 
of false swimming feet beneath the abdomen. 
Oss. This genus is composed of minute species. M. Milne-Edwards suspects that this and 
its allied genus Megalops may possibly include merely the young of some other crustacean, 
They form the passage from the Decapoda anomoura to the D. macroura. 
M. inermis. (Say, Acad. Nat. Sc. Vol. 1, p. 157.) Front unequal, extended into a short rostrum, with 
a tooth on each side near the eyes. A large truncate tubercle behind each eye. Tarsi simple, 
Hind feet very small, terminated by three sete. Color, olive green. Length of thorax, 0+25. 
Eastern shore of Maryland. 
M. spinitarsus. (Savy, loc. cit. Vol. 1, p. 58.) Tubercle behind the eyes obsolete. T'arsi armed beneath 
with about seven rigid spines, of which the fifth is largest and the sixth smallest; the tip incurved, 
acute, Length of thorax, 0°3. Coast of South-Carolina. 
* Dr. Leach (Nowv. Dict, des Sc. Vol. 18, p. 54) has arranged this and a few others under a subdivision of Porcellana, 
which he calls Pisidia, but which has not been adopted by many subsequent writers, He calls it Pisidia sayana, and 
describes “the shield and pincers marked with short and transverse lines; front trifid, with the elongated medial oneitself 
tridentate and finely granular.” The P. galathina of Bosc, is supposed by Dr. Leach to be different, and more closely 
allied to the sociata, and he adds the following characters: Shield striate ; front smooth and undivided ; pincers large, equal, 
chagrined above, with three very sharp spines on the inside; hands nearly triangular ; fingers short, without any denta_ 
tions within, 
