22 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
of only two segments, of which the terminal one is large. Chelipeds of moderate size; fingers longi- 
tudinal. The ambulatory legs are small and differ little in length; dactyli of three anterior pairs 
bifurcate, those of posterior pair simple. In the male the sternum is Hat. and very broad, breadth 
between posterior legs much more than twice as great as breadth of basal segments of abdomen. Male 
abdomen narrow and only three-jointed, the first and second segments anchylosed, and the third, 
fourth, fifth, and sixth also united in one piece; in the female abdomen the segments are all free. 
I recently established the genus Echinophilus on a cursory examination of specimens called 
E. mellitx, supposing the palpus of the maxillipeds to consist of three joints instead of two; now 
having discovered my error, I place the type species, as well as the one here described, in the genus 
Dissodactylus. 
Dissodactylus encopei, sp. nov. 
The carapace is about 1.4 times as wide as long, the posterior width is but little less than 
the greatest, width and much greater than the antero-lateral margins The dorsal surface is naked 
and polished, is convex antero-posteriorly, and slightly so in the opposite direction. The antero- 
lateral margins are marked by a distinct line, which, after turning the lateral angle, runs up a little on 
the dorsal surface. The frontal and antero-lateral margins have also a fringe of fine hair. Posterior 
margin slightly concave at the middle, convex toward the sides. The inner distal angle of the 
terminal segment of maxilliped fits against the inner angle of the merus joint; this angle is thickened 
and densely clothed with hairs. Outer surface of chelipeds crossed by a few short oblique ridges, 
from which short appressed hairs proceed distally; margins on inner surface of segments also fringed 
Fig. 5 . — Dissodactylus encopei, ma,\e. (a) Outline of carapace, 4. (b) Maxilliped, x 12.8. (c) Chela, 10.66. 
(d) Fourth leg, x 10.66. (e) Fifth leg, 10.66. 
with hair, while a longitudinal row of hairs is near the lower margin. Arm short, nearly as broad as 
long, and of about the same size as wrist; hand thick and subc.ylindrical; fingers nearly as long as 
palm and feebly dentate; they lit closely together, curve inward, and the tips are bent toward each 
other, and cross. Ambulatory legs short (their length less than width of carapace), and rather narrow 
and smooth, with hairy margins. Dactyli of first three pairs bifid at extremity. Dactyli of last pair 
simple, styliform, and acute. First segment of male abdomen narrower than second, being scarcely 
more than one-third the width of adjacent sternum; margins of second segment slightly convex; the 
segment tapers toward extremity; terminal segment equi laterally triangular and obtuse. 
Length of male, 4.6 mm.; width, 6.6 mm. Length of female, 5 mm.; width, 7 mm. 
Several specimens of this species were taken at Stann Creek, 38 miles south of Belize, British 
Honduras, by the Rev. W. A. Stanton, S. .T. ; they were attached to the lower surface of Encope emur- 
yinota (Leske); Cat. No. 23430, types. 
A single young male, 27 mm. wide, was taken by the Eisli Hawk- in 11 fathoms, off Vieques, 
station 6084. It agrees with the types, except as to the ambulatory legs, which are relatively wider; a 
larger series is necessary to determine its identity with certainty. 
This species has quite a different aspect from the type species, D. nitidus, being much wider, 
more convex, with the bifurcation of the dactyli less deep and less conspicuous. D. mellitse is a convex 
species but somewhat narrower than I), encopei, being 1.33 broader than, long; dactyli more deeply 
bifurcate. It is probable that the bifurcation of the dactyli is for the purpose of more ready attach- 
ment to foreign bodies, as two of the species are known to be commensal with sea-urchins. 
