140 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
peduncles of the antennuhe are but little longer than the eyes, while the peduncles of the antenna? are 
about equal in length; the acicles are curved in about the same lines as the eyes. 
The right cheliped is moderately stout; the merus has a slender spine above on the anterior 
margin; there are two on each side of the lower margin. There is a row of six spines on the 
inner margin of the carpus, and seven or eight spines on the upper surface, not arranged in well- 
defined rows. The hand is oblong-ovate, with six well-defined rows of spines., two of which occupy 
the margins; a row runs parallel to the inner margin; this and the marginal row are continuous with 
two rows on the dactyl; the two median rows converge to a common terminal spine near the gape 
of the fingers; the sixth row runs in a curve to a point near the end of the immovable finger; the lower 
surface of the palm is smooth. The hand is hairy and in the shell, covered with mud which clings 
to the hair and the surface between the s]>ines. The left hand is very much smaller than the right; 
is slender, the hand being but a trifle wider than the carpus. The carpus is compressed and is armed 
with a few spines on the upper margin. Those on the distal end are the largest. The hand is 
a. Right hand. 
Front and anterior appendages 
of P. marshi. 
!>, Left hand. 
elliptical in shape with a hiatus between the fingers; a line of spines runs along the outer margin to 
the end of the immovable finger; another line begins at the inner angle of the articulation with the 
carpus and runs across the palm to the end of the immovable finger. A short line runs from the 
opposite angle to the gape of the fingers. This combination of lines incloses an elliptical space, 
which is smooth or with one or two spines. The ambulatory legs are hairy. 
Obtained at Ponce, in shells of Turbo caslcmeus Lamarck. 
Named for Mr. Millard C. Marsh, of the scientific staff of the Fish Hawk, on its expedition to 
Porto Rico. 
Genus PETROCHIRUS. 
Petrochirus bahamensis (ILerbst) 
Cancer bahamensis Catesby, Carolina, p. 34, pi. xxxiv; Herbst, II, p. 30, 1792. 
Pagurus granulatus H. Milne Edwards, Hist. Nat. des Crust., n, p. 225, 1837. 
Petrochirus granulatus Stimpson, Proe. Acad. Nat. Set. Phila. 1858, p. 223. 
Two small specimens of this species were taken, one at Mayaguez, the other at Boqueron Bay. 
This is the common hermit inhabitant of the large conch Sir ombus gigas, so frequently met with in 
the shallow waters of Florida and the West Indies, and is perhaps the largest of the Paguridx. 
The front extends forward between the bases of the outer antenna?; the lateral projections are a 
little in advance of the middle or rostral projection; the outer amen life are placed in an angle of the 
front. The anterior portion of the carapace is about as broad as long; is rough and uneven at the 
sides, with'now and then a bunch of stiff bristles. The length of the eyes measured from the front 
to the extremity of the cornea equals that of the anterior portion of the carapace. A small 
cuneiform spot of red seems to be uniformly found on the peduncle just below the cornea on the inner 
