OXYSTOMATOUS AND ALLIED CRABS OF AMERICA 5^ 



HYPOCONCHA CAUFORNIENSIS Bouvier 



Plate 10, Figures 3, 4 



Hypoconcha californiensis Bouvier, Bull Mus. Hist. Nat,, Paris, vol. 4, p. 374, 

 1898 (type locality, San Jose Island, Gulf of California; type in Paris Mus.). 



Diagnosis. — Margin of carapace with short, dense hairs. Merus of 

 maxilliped sub triangular, its anterior margin longer than the lateral 

 margin and as long as the two preceding articles united. Carapace 

 slightly pilose below. 



Description. — The subacute teeth bordering the carapace number 

 three on each median frontal lobe and six on each side between the 

 superior orbital notch and the point where the carapace is widest; 

 the inferior orbital border has five spines on each side. Median 

 furrow of frontogastric region scarcely indicated. The anterolateral 

 walls of the buccal cavity present a strong flap directed inward, 

 upon which is supported the anterior border of the merus of the outer 

 maxilliped; the upper wall of the endostome is armed on either side 

 with a prominent ridge, which has a denticle at its middle. Merus of 

 outer maxillipeds three times as wide on the anterior border as on the 

 border in contact with the ischium; length of merus equal to that of 

 the two basal articles together. Chelae \vith numerous tubercles on 

 outer face; some almost continuous (on thumb and neighboring 

 palm.ar portion), some widely separated; they become very small on 

 the lower border where they form an inconspicuous longitudinal 

 row; a stronger tubercle, terminating in two points, occupies the 

 middle of the external base of the hand. The greater number of these 

 tubercles are acute or subacute; they occur also on the flat outer face 

 of the carpus, where they form two rows which converge a little from 

 behind forward. (After Bouvier.) 



Color. — In formalin a uniform reddish. 



Measurements. — Female, type, length of carapace 12.5, width 13.5 

 mm (Bouvier). Male (42224), length and width 6 mm. 



Range. — Gulf of California, Mexico, to Panama. 



Material examined. — Off Cerralvo Island; lat. 24°11'30" N., long. 

 109°55'00" W.; 10 fathoms; shells; April 30, 1888; station 2828, 

 Albatross; 1 male (42224). Panama: Near Changone, Taboga Island, 

 dredged December 24, 1933; 1 male, 1 female (69407); E. D. Robson 

 collector. 



Family DYNOMENIDAE Ortmann 



Dynomenidae Ortmann, Zool. Jahrb., vol. 6, p. 541, 1892; in Bronn's Klassen und 

 Ordnungen des Thier-Reichs, vol. 5, pt. 2, Arthropoda, p. 1155, 1901. — 

 Alcock, Journ. Asiat. Soc. Bengal, vol. 68, pt. 2, p. 127, 1899; Catalogue of 

 the Indian decapod Crustacea in the collection of the Indian Museum, fasc. 

 1, p. 34, 1901. 



Dynomeninae A. Milne Edwards and Bouvier, Crustac^s d^capodes provenant 

 des campagnes du yacht V Hirondelle (supplement) et de la Princesse-Alice, 

 fasc. 13, p. 9, 1899; Mem. Mus. Comp Zool., vol, 27, p. 22, 1902. 



