THE BRACHYURA AND MACRURA OF PORTO RIOO. 
47 
Portunus (Achelous) spinicarpus Stimpson. 
Achelous spinicarpus Stimpson, Bull. Mus. Comp. Zool., ir, 148, 1871. 
Neptunus spinicarpus A. Milne Edwards, Crust. R6g. Mex., 221, pi. xl, f. 1, 1879. 
Carapace narrow, slightly pubescent, surface uneven. Antero-lateral teeth very sharp and slender. 
Lateral spine very long and slender, about half the length of lateral border. Front slightly advanced, 
teeth small, sharp, triangular; median surpassing a little the lateral. A notch in inner orbital tooth 
above flagellum. Postero-latei’al angles sharp. Chelipeds long and feeble. Merus armed in front with 
four large spines, a fifth spine at end of posterior margin. Wrist with an unusually long spine, reaching 
anterior third of the hand, or even beyond end of palm. Palm with only two small spines. Swimming 
feet large and strong, merus with infero-distal angle spinulous. Sternum finely granulate; abdomen 
smooth. 
Dimensions of male: Length to sinus, 20.5 mm.; extreme length, 21.2 njm.; extreme width, 
45.2 mm.; width to sinus in front of lateral spine, 32.5 mm. 
From North Carolina to Sabanilla, United States of Colombia, and Trinidad, 13 to 150 fathoms. 
Mayaguez Harbor, Porto Rico, 75 to 76 fathoms, station 6063. 
Genus CALLINECTES Stimpson. 
Callinectes Stimpson, Ann. Lyc. Nat. Hist. N. Y., vn, 220, 1860. 
The genus Callinectes is opposed to Portunus by having the abdomen of the male very narrow, 
1-shaped, and the merus of the outer maxillipeds strongly produced outwardly at antero-external 
angle. The different species also agree in having strong antero-lateral teeth, the last being consider- 
ably stronger than the others, and in the stout chelipeds, the manus having five external costae and 
not more than two teeth or spines. 
Key to the Porto Rican species of the genus Callinectes. 
A. Frontal teeth two (excluding the inner orbital) t sapidus acutidens 
A'. Frontal teeth four (excluding the inner orbital). 
B. Appendages of first abdominal segment of male much shorter than abdomen. 
C. Lateral spine more than twice the length of preceding tooth. 
D. Intramedial region broad, its anterior width about three times its length ornatus 
D'. Intramedial region narrow, its anterior width about twice its length. 
E. Appendages of first abdominal segment of male greatly exceeding third segment danx 
E'. Appendages exceeding third segment but little, or not at all marginatus 
C'. Lateral spine less than twice the length of preceding tooth exasperatus 
B'. Appendages reaching the extremity of abdomen bocottrti 
Callinectes sapidus acutidens Rathbun. 
Callinectes sapidus acutidens Rathbun, Proc. U. S. Nat. Mus., xvii, 354, pis. xm and xiv, f. 2, 1895. 
Carapace moderately convex. Granules prominent, crowded on inner branchial and cardiac 
regions, more scattered on anterior half of carapace. Length of intramedial region about one-half its 
anterior width. A transverse granulate ridge on protuberant cardiac lobes. Two triangular frontal 
(interantennal) teeth, each having on its inner margin a low ill-defined tooth whose outer margin is 
transverse. Subfrontal and suborbital spines acuminate. Lateral teeth broad at base, narrowing 
abruptly to long, acuminate tips; margins granulate. Last two teeth very long; lateral spine more 
than three times the length of preceding tooth. Penultimate segment of abdomen of male much 
constricted in its proximal half, widening at both extremities. Terminal segment obtuse, lateral 
margins convex proximally, slightly concave or straight distally. Appendages of first segment reach 
nearly to or beyond extremity of abdomen, near together for their proximal half, with only a slight 
outward curve; distal portions widely divergent except at tips. Abdomen of adult female very broad, 
margins of last three segments separately convex; terminal segment longer than wide. Costae of ehel- 
iped very prominent and strongly granulate. The granules of inner margin of merus extend upon upper 
surface of distal half. Two carpal spines, one at outer angle and a shorter one close to propodal spine. 
Length of male, 49 mm. ; total length, 50.8 mm. ; width, 121 mm. ; length of lateral spine, 16 mm. ; 
of preceding tooth, 5 mm. 
Santa Cruz and Rio de Janeiro, Brazil; Escondido River and Greytown, Nicaragua; St. Johns 
River, Palatka, Florida; Lake Palourde, Morgan City, Louisiana (not typical). Porto Rico: Arrovo, 
1 young male; Mayaguez Harbor, 7 fathoms, station 6059, 1 adult female, without chelipeds. 
