THE BRA OH Y UR A AN I, MACRURA OE PORTO RICO. 
15 
Cardisoma guanhumi Latreille. 
Cardisoma guanhumi Latreille, Encyc. M6th., Hist. Nat., Inseetes, x, 685, 1825. 
Carapace of male very large, about four-fifths as long as wide, much swollen outside lateral margin, 
which is either faintly or distinctly indicated; a notch behind outer orbital angle. Front wider than 
orbit, bent down, with a broad median sinus on its margin. The chelipeds are extremely unequal, the 
larger one very powerful, tuberculate along margins of both cliche; lingers of large chela widely gaping. 
Ambulatory legs spinous. The chelipeds of the female are also unequal, but much less so than in 
the male. 
Length of male from San Juan market, 77 mm.; width, 94 mm.; width between outer orbital 
angles, 68 mm. ; posterior width of front, 28 mm. 
Bahamas; Florida Keys to Brazil ; Bermudas (Rankin). Porto Rico: Collected by the Fish Com- 
mission at Catano; San Juan market; Rio Bayamon, above Palo Seco. Porto Rico (Gundlach). 
Its common name in Porto Rico is “ Juey” (San Juan market). 
Family GRAPSID 7 E Milne Edwards, 1837. 
Carapace depressed or moderately convex, more or less quadrilateral, with the lateral margins 
straight or slightly arcuate. Front never very narrow, in general decidedly broad. Orbits and eye- 
stalks of moderate size. Third maxillipeds with the palpus articulated at the apex or at the front 
outer angle of the merus. Chelipeds in adult male usually subequal, moderately developed. In the 
walking legs the seventh joint is styliform, compressed, and either smooth or spiniferous. The pleon 
at the base usually covers the whole width of the sternum between the last pair of legs. 
Key to the Porto Rican genera, of the family Grapsidee. 
A. Antennee covered by the front. 
B. Externa] maxillipeas without a piliferous ridge. 
C. Antennae excluded from the orbit Goniopsis 
C'. Antennae entering the orbit. 
D. Merus of maxillipeds longer than broad. 
E. Fingers spoon-shaped at tips Grapsus 
E'. Fingers acute .' Geograpsus 
1)'. Merus of maxillipeds as broad as long Pachygrapsus 
B'. External maxillipeds with a piliferous ridge. 
C. Lateral margins straight, 
D. Carapace elongate, very narrow behind ...Aratus 
D'. Carapace transverse, usually quadrate Sesarma 
C'. Lateral margins arcuate and entire Cyclograpsus 
A'. Antennae visible from above. 
B. Merus of maxillipeds large, as broad as ischium Plagusia 
B'. Merus of maxillipeds small, much narrower than ischium Percnon 
Genus GONIOPSIS de Haan. 
Goniopsis de Haan, Fauna Japon., p. 5, 1833; p. 33, 1835. 
Carapace flat; front vertical, over half as wide as carapace; sides straight, with one tooth. Sub- 
orbital lobe broad, reaching the front and excluding the antenna from the orbit. External maxillipeds 
narrow; merus and ischium of equal length. 
Goniopsis cruentata (Latreille). Mangrove Crab. Plate 1. 
Grapsus cruentatus Latreille, Hist. Nat. Crust,, vi, 70, 1803. 
Grapsus ( Goniopsis ) cruentatus de Haan, Fauna Japon., 33, 1835. 
Front granulate, suprafrontal lobes four, margins crenulate, orbits entire above, two notches 
below on outer half. Carapace with oblique ridges on branchial regions, transverse ridges anteriorly. 
Anterior margin of merus of chelipeds expanded, dentate, the upper and lower margins with spiniform 
tubercles, as is also the upper margin of carpus. Hands with spiniform tubercles above and below, 
the middle of the outer surface smooth, the inner surface with scattered prominent tubercles. Thumb 
