264 BULLETIN OF THE 
in breadth. The front is nearly straight, the branchial regions expanded 
laterally so as to form a prominent shoulder at the point where they meet the 
hepatic areas. A row of small, irregularly disposed spines on the sides of the 
carapace. The second and third pairs of maxillipeds (Figs. 6, 7) have the same 
structure as in adult Pinnixe, the terminal segment of the inner limb being 
articulated with the penultimate segment near the proximal end of the latter, 
in such a fashion as to form a sort of didactyle claw. 
The chele are didactyle, the dactylus closing against a long process of 
the antecedent segment. The following pairs of ambulatory appendages are 
extremely long, the last pair being much smaller than the rest, as in the adults 
of this genus. 
The abdomen is small, closely folded against the sternum, and not used as a 
swimming organ. It carries four pairs of appendages (Fig. 3), which consist 
of a basal segment which supports two branches, The outer branch is much 
larger than the inner, and bears about nine sete on its border. The telson is 
broader than long, its posterior margin regularly convex and fringed with sete. 
Blotches of dark pigment, of dendritic forms, occur on the carapace, sternum, 
and abdomen, arranged as represented in Figs. 1, 2. 
The young crabs underwent hardly any change during my stay at Newport, 
and it is impossible to determine to which of the several species of Pinnixa, 
described from the eastern coast of the United States, these immature speci- 
mens belong. According to Smith, the only species found on the New Eng- 
land coast is Pinniza cylindrica White.* I found no adult specimens at New- 
port. 
Since the above account was prepared, T have received, through the courtesy 
of Professor Smith, a pair of adult Pinniae from Buzzard’s Bay, Massachusetts, 
and a few zoém “hatched at Noank, Connecticut, August 3, 1874, from eggs 
of a specimen apparently exactly like the adults sent.” I identify the adults 
with Pinniza chotopterana Stimpson T (Plate V. Fig. 8, chela of male ; Fig. 
9, chela of female). The zoéw (Plate TV. Figs. 1-4) are less than a milli- 
meter in length. The spines of the carapace are proportionately shorter than 
in the older zoéa described above, the swimming-fect and abdomen longer. 
The appendages back of the second pair of maxillipeds are wanting. The 
abdomen is very like the abdomen in the older zoéa, but has a small, trian- 
gular, terminal piece (Fig 2 0) between the sete of the telson. 
Professor Smith informs me that he observed, in 1875, the direct change 
* Report upon the Invertebrate Animals of Vineyard Sound and Adjacent Waters, 
with an Account of the Physical Features of the Region. By A. E. Verrill and $. I. 
Smith. In Baird’s Report on the Condition of the Sea-Fisheries of the South Coast 
of New England in 1871 and 1872, p. 546. 1873. 
+ Notes on North American Crustacea in the Museum of the Smithsonian Insti- 
tution. No, Il. Ann. Lye. Nat. Hist, N. Y. Vol. VIT. p. 235. 1802. 
