BULLETIN OF THE UNITED STATES FISH COMMISSION. 
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granules, while the surface near the opposite margin is set with ridges and compressed granules, which 
appear like little disks on edge. The granules of the middle of the carpus are very much depressed. 
The surface of the palm is thickly set with coarse granules; near the crest the granules are smaller. 
The elevated portion of the crest is longer than in P. glabra and about the same as in V. angnstifrons. 
On corals at Mayaguez. 
This species, like all others of the genus that I have seen, is small, the larger specimens not 
measuring more than 5 mm. in width. 
Genus PACHYCHELES. 
Pachycheles rugimanus A. Milne-Edwards. Plate 3, fig. 9. 
Parity elides rugimanus A. Milne-Edwards, Bull. Mns. Comp. Zool., vin, p. 3G, 1880-81. 
The outline of the frontal margin as seen from above is nearly straight; from in front the margin 
dips down in a v at. the median line. The orbits are raised, forming a depression behind the margin. 
The chelipeds are subequal; the inner margins of the carpal segments are armed with four teeth, graded 
in size, the proximal being the largest; the upper surfaces have four longitudinal ridges, with deep 
channels between; the channels are interrupted at the bottom by septic, which form a row of oblong 
pits between the ridges. The hands have the same general character, except that there is less 
regularity in the arrangement. The dactyls of the ambulatory feet are short and are armed beneath 
with three or more small spines, too small to warrant the term multiungulate. 
Dredged by the Blake. 
Pachycheles ackleianus A. Milne-Edwards. 
Pachychdes ackleianus A. Milne-Edwards, Bull. Mus. Comp. Zool., vm, p. 3G, 1880-81. 
The front is nearly vertical and straight as seen from above; from before the median projection it is 
short and triangular. The carapace is longer than wide, with nearly parallel sides; a prominent suture 
crosses it from side to side, running behind the hepatic and gastric regions. The chelipeds are very 
unequal in size; the left is much the larger in one specimen, while the reverse is true in two others. 
The carpal segment of each is armed with three stout teeth on the inner margin. The surfaces are 
dotted with large flattened granules, without any regular arrangement; the granules on the hand are 
similar, except on the lower margin, where they are regularly elongated and are arranged in rows; a 
bunch of granules near the gape of the fingers forms a prominent tubercle. The dactyls are short, 
wide, and multiungulate, as in Polyonyx Stimpson, and like the type species of that genus it is 
commensal in its habits, having been found by Mr. J. E. Duerden “in massive black sponges.” In 
appearance and in the character of the antennae it is a Pachycheles. 
U. S. Fish Commission steamer Albatross, station 2413. 
Genus MEGALOBRACHIUM. 
Megalobrachium poeyi (Guerin). Plate 3, fig. 8. 
Porcellana poeyi Gufrrin, La Sagra’s Hist, of Cuba, vm (Atlas), Articulata, pi. ii, fig. 4, “1855.” 
Megalobrachium granuliferum Stimpson, Proe. Acad. Nat. Sci. Phila., x, p. 228,1858; also Annals Lye. Nat. Hist. New York, vn, 
p. 70 (March, 1859) . 
The three lobes of the front extend but little beyond the eyes; the middle lobe is rounded, not 
noticeably larger and but a trifle in advance of the lateral lobes, which are more angular. The eyes 
are small. The carapace is rounded; there is a paired depression behind the eye on the gastric region. 
The areolations are distinct; the surface is pubescent, often covered with sordes; along the front, 
between and a little behind the eyes, and along the antero-lateral region the surface is sharply granular; 
a part of the border is marked by a row of granules. The chelipeds are characterized by depressions— 
two on the carpus and three on the palm. The entire surface is more or less hairy and is coarsely 
granulated. The hair on the lower portion of the palm and on the fingers is long and coarse and is 
often covered with dark slime. 
Taken among the Bahama Islands at St. Thomas, the Barbados, and at Savanilla. 
