Kingsley.] 158 [March Dy 
OCYPODOIDEA. 
Family GRAPSIDZ. Sub-Family GRAPSINZ. 
Genus PACHYGRAPSUS Randall, Stimpson. 
Pachygrapsus transversus Gibbes. 
Grapsus transversus Gibbes, Proc. Am. Assoc. Adv. Sci., 11, 181 
(1851). Pachygrapsus transversus Gibbes, 1. c., 182, Stimpson, An- 
nals N. Y. Lye., vi1, 64 (1859); zbid, J. c., X, 113 (1871); Smith, 
Report Peabody Acad. Science, 11, 91 (1871). Metopograpsus 
dubius Saussure, Crustacés Antilles, Mexique et Etats Unis, p. 29, pl. 
11, f. 16 (1858). Metopograpsus miniatus Saussure, I. c., p. 28, pl. 11, 
f. 17, (1858). 
Carapax smooth, shining, with crenulated transverse ridges, oblique 
on the branchial regions. Supra-frontal lobes prominent, but not so 
much as in specimens of P. plicatus from Tahiti. Front sinuate, 
making with the inner margin of the orbit a right angle, and viewed 
from in front, undulating. Orbits with the inferior margin making a 
sharp angle with the external tooth. A single acute tooth on the 
lateral margin, margin generally arcuate. The meros of the exter- 
nal maxillipeds is as broad as long, chelipeds unequal; meros crossed 
by crenulated ridges similar to those on the carapax, inner distal mar- 
gin armed with from three to five acute teeth; carpus with the ridges 
less distinct, a prominent rounded tooth on the inner surface; hand 
minutely granulate, margins rounded; a ridge runs on the lower outer 
surface from near the base of the palm to the extremity of the pollex; 
fingers slightly gaping, smooth above and below, the occludent mar- 
gins finely toothed. Posterior feet with the distal inferior angle with 
two to four teeth; meros of the first three pairs with a sharp ridge on 
the anterior and posterior margins; meral and propodal joints of all 
the ambulatory feet with long hairs; dactyli spinose, stout and with 
scattered long hairs. 
In examining fifty-five specimens of Pachygrapsi brought from Key 
West, Florida, by Dr. Packard, I found forty-nine specimens which 
I referred without a doubt to P. transversus, four to P. gracilis and two 
doubtful ones which resemble Saussure’s description and figure of 
Metopograpsus miniatus. 'These have the narrower front and slightly 
more arcuate lateral margins, but I can hardly consider them as dis- 
tinct from P.transversus. In the above forty-nine specimens of P. trans- 
versus I found a variation in the arcuation of the lateral margin, and 
