no.1766. STALK-EYED CRUSTACEA OF PERU—RATHBUN. 549 



Near Capon, February 2. "Cangrejos de los manglares." Commonly seen climb- 

 ing on the mots and branches of the mangroves, sometimes entering holes in its mud 

 (which may, however, pertain to other species of crabs). 



Not previously known from Peru. 



Distribution. — From Nicaragua to Peru; also on the east coast of 

 America.. 



CARDISOMA CRASSUM Smith. 



Plate 4 I . 



Cardiosoma crasswm Smith, Trans. Conn. Acad. »Sci., vol. 2, 1870, p. 144, pi. 5, 

 fig. 5. 



Of huge size. Carapace thick, convex, subcordate, deeply fur- 

 rowed, otherwise smooth. "Front truncate, about one-fourth as wide 

 as carapace. Eyes stout, moderately long, in large triangular orbits. 

 Merus of outer maxillipeds notched at summit. Chelipeds massive, 

 very unequal, mostly smooth, margins tuberculate or bluntly spinous, 

 larger claw longer than width of body, its fingers gaping, armed with 

 strong prehensile teeth. Terminal joint of legs spinous. 



Width about 125 mm., length of large claw about 150 mm. 



Mouth of River Tumbes, February 12. The "Cangrejo sin boca" (mouthless crab), 

 an inappropriate and inexplicable name. 



Not previously known from Pent. 



Distribution. — From La Paz, Lower California, to Peru. 



UCIDES OCCIDENTALIS (Ortmann). 

 Plate 42, fig. 2. 



Uca Him Milne Edwards and Lucas, d'Orbigny's Voy. Amer. Mer., vol. 0, 



pt. 1, 184:5, p. 2:5. 

 Uca laevis Milne Edwards, Arch. Mns. Hist. Nat., Paris, vol. 7, 1854, p. 185, pi. 



Hi, figs. 1 and la. 

 CEdi pleura occidentalis Ortmann, Zool. Jahrb. Syst., vol. 10, 1897, p. 336. 



Of large size. Sexes very unlike. Carapace thick, very convex, in 

 male 1 1 a itsverselyoval, in female much narrower and with a well-defined 

 marginal line. Front narrow, arcuate, bent down. Eyes of moderate 

 length, nearly filling orbits. Merus of outer maxillipeds quadrate, 

 not notched at summit. Chelipeds of male very long, nearly equal, 

 very spinous on the margins and inner surface. Palms longer than 

 the broad, flat, narrowly gaping fingers; chelipeds of female much 

 shorter, relatively broader, very unequal, similarly roughened, palm 

 not noticeably longer than fingers, which gape widely in larger claw. 

 Legs margined with fringes of hair, especially beneath; terminal joint 

 unarmed. 



Width of male about 95 mm., of female about 75 mm.: length of 

 longer cheliped of nude about 23 cm. 



From the mangrove swamps at Las Vacas in the region of Capon, January 2:;, 1908. 

 This is the "cangrejo" abundant in the mud of the mangrove swamps of the region. 



