THE BRACHYURA AND MACRURA OF PORTO RICO. 
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having the appearance of two spines, one above the other, soldered together; no elevated transverse 
ridge connecting these spines, and only a tubercle on the median line behind the carapace. Chelipeds 
of male longer than those of df. subparallelum; hands with small papillose tubercles above and inside. 
Ambulatory legs slender. 
Dimensions of male: Length, 37 mm. ; width, 29 mm. 
Bahamas; West Indies. Depth, 3 to 13 fathoms. Porto Rico: Playa de Ponce Reef; Ensenada 
Honda, Culebra. 
Macrocoeloma concavum Miers. 
Macrocoeloma concava Miers, Challenger Rept., Zool., xvn, 81, pi. x, f. 2, 1886. 
Macrocoeloma concavum Rathbun, Proc. U. S. Nat. Mus., xxi, 576, 1898. 
Body and legs covered with a short, close pubescence, with some longer curled hairs. Carapace 
very convex, deeply concave upon hepatic regions; dorsal surface armed with ten spines, disposed as 
follows: Three small spines in a triangle upon gastric region, of which the posterior and median one 
is the largest; two small spines on cardiac region, one on intestinal region close to posterior margin; a 
spine on dorsal surface of each branchial region and a rather strong lateral spine; a few tubercles in 
front of median gastric spine. Lateral margins of carapace tuberculated, the tubercles continued in an 
oblique series over pterygostomian regions nearly to antero-external angle of buccal cavity. Spines of 
rostrum strongly deflexed, short, flat, nearly straight, divergent, separated by a triangular interspace. 
The tubular orbits are laterally much elongated and bear small spines or tubercles, placed one in front 
of and one behind the eye, and between them above and below two tubercles. Basal antennal joint 
equaling in width the base of rostrum and bearing several tubercles on outer margin, and two spines, 
one at distal extremity and one on outer margin. Chelipeds in male rather slender and elongate, arm 
unevenly granulate and tuberculate on margins; wrist with a small tubercle on inner margin; palm 
slightly compressed, not dilated nor carinated, granulated on its inner surface; fingers about half as 
long as palm, bent downward, curved, meeting only toward the tips, and minutely denticulated on 
their inner margins. 
Dimensions of adult female from station 6091: Entire length, 37 mm.; greatest width, 33.2 mm.; 
width at orbits, 21.5 mm.; length of rostral spines, 4.4 mm. 
Brazil: Off Cape St. Roque, 20 fathoms; Bahia, shallow water (Miers); Fernando Noronha, 7 to 
20 fathoms (Miers). Off Vieques, 12) to 15 fathoms, stations 6091 and 6095. 
There are three closely allied West Indian species with elongated tubular orbits and two antennal 
spines: M. eutheca (Stimpson), in which the rostral spines are separated by a U-shaped sinus, and the 
orbits are prolonged far beyond the antennal spines; M. concavum Miers, described above, and 
M. intermedium sp. no v. 1 =M. eutlieca. Rathbun, 1892, 2 not Stimpson, which, like M. concavum, has a 
triangular space between the horns, but lacks the anterior cardiac spine and has a greater breadth 
across the base of the rostrum. 
Genus LEPTOPISA Stimpson. 
Leptopisa Stimpson, Bull. Mus. Comp. Zool., II, 114, 1871. 
Carapace narrow, oblong, tuberculated, with an epibranchial spine, but no lateral series of spines. 
Orbits complete, short, tubular. Spines of rostrum long and slender. Basal joint of antenna enlarged, 
armed with spines distally; movable part of antennae very slender and partly hidden by rostrum. 
Buccal cavity very wide; merus of outer maxillipeds strongly dilated laterally, wider than ischium 
and notched at inner angle. Chelipeds slender, elongate. Ambulatory legs decreasing regularly in 
length, the first pair very long, last pair very short. 
Closely allied to Macrocoeloma, from which it differs chiefly in its narrow carapace, long horns, 
and short orbital tubes. 
Leptopisa setirostris Stimpson. 
Tiarinia setirostris Stimpson, Bull. Mus. Comp. Zool., II, 114, 1871. 
Leptopisa setirostris Stimpson, Bull. Mus. Comp. Zool., ii, 114, 1871, in text. 
Macrocoeloma tenuirostra Rathbun, Proc. U. S. Nat. Mus., xv, 252, pi. xxxm, f. 1, 1892. 
Carajiace covered with a short pubescence, and numerous depressed tubercles; cardiac region 
with a prominent tubercle; mesogastric region with one less high; intestinal region with two short 
median spines; a short, sharp spine at postero-lateral angle of branchial region; lateral margins nearly 
straight, tuberculate; sides perpendicular. Orbit with a short preocular and postocular spine and an 
inferior tubercle on margin of antennal joint. Rostral horns about half as long as rest of carapace, 
1 Type, U. S. Nat. Mus. Cat. No. 9492, off Ilabana, 163 fms., station 2323, Albatross. 2 Proc. U. S. Nat Mus., xv, 251, 1892. 
