no. 176G. STALK-EYED CRUSTACEA OF PERU—RATHBVN. 545 



SPEOCARCINUS OSTREARICOLA, new species. 



Plate is, fig. 2. 



Of small size. Body and legs coarsely hairy. Carapace subcylin- 

 drical. transverse, granulate, antero-lateral margin arcuate, triden- 

 tate. Front equal to one-fourth width of carapace. Eye-stalks dis- 

 tally slender, filling orbits. Chelipeds unequal, broad, nearly smooth ; 

 a tooth on upper edge of arm and inner edge of wrist; palm high, fin- 

 gers narrowly gaping, toothed. Legs narrow, third pair longest; 

 dactyli nearly straight, prismatic. 



Width of type male 17.6 mm., length 12 mm. 



In S. granulimanus Rathbun a of Lower California, which is nearly 

 related to the above species, the carapace is narrower, side teeth 

 smaller, hands and wrists coarsely granulate. 



Ti/pe-locality-. — Oyster beds of Matapalo (near Capon), January 

 23, 1908. 



Type.— Vat. No. 40469, U.S.N.M. One male. 



OSTRACOTHERES POLITUS Smith. 



Plate 43, fig. 3. 



Ostracotheres politus Smith, Trans. Conn. Acad. Sci., vol. 2, 1870, p. 169. — Lenz, 

 Zool. Jahrb.. Suppl. vol. 5, 1902, p. 70."), pi. 23, figs. 9 and 9a. 



Small. Carapace thin, flattened, smooth and shining; trans- 

 versely oval; front not projecting; a median sulcus on front and a 

 U-shaped sulcus extending from orbits to middle of carapace. Ialp 

 of outer maxilliped two-jointed. Chelipeds equal; segments rounded, 

 smooth; hands compressed; fingers not gaping; dactylus with basal 

 tooth. Legs short, cylindrical; dactyli of first three pairs short and 

 curved, dactyli of first and second pairs folding against the expanded 

 distal end of propodus which is clothed with hair; fourth pair of 

 legs much the slenderest, dactylus slightly curved and as long as the 

 propodus. 



Width 7 to 14 mm. 



Found with Crepidula-like form [C. dilatata] on mussels taken in Ancon Bay. 

 Distribution. — Peru ; Chile. Living within shells of mollusks. 



DISSODACTYLUS NITIDUS Smith. 

 Plate 48, fig. H. 

 Dissodactylus nitidus Smith, Trans. Conn. Acad. Sci., vol. 2, 1870, p. 17:?. 



Of small size. Carapace transversely oblong, flattened, smooth. 

 Front narrow; eyes minute. Buccal cavity broad behind, arched 

 anteriorly, very nearly reaching the front. Palate not divided by a 

 median ridge. Ischium and merus of outer maxillipeds coalesced, 

 palpus of two segments, the terminal one large and spatulate. Cheli- 



"Proc U. S. Xat. Mus., vol. HI, ls!i:i, p. 2 12. 

 Proc. N.M. vol . 38— 1 35 



