THE SPIDER CRABS OF AMERICA 113 



COLLODES TENUIROSTRIS Rathbun 



Plate 37 



Collodes tenuirostris Rathbun, Proc. U. S. Nat. Mas., vol. 16, 1893, p. 230 

 (type-locality, Gulf of California, lat. 30° 16' N., long. 113° 05' W., 36 

 fathoms; holotype, Cat. No. 17333, U. S. N. M.); Proc. U. S. Nat. Mus., 

 vol. 21, 1898, p. 569. 



Collodes, doubtful species, Rathbun, Proc. U. S. Nat. Mus., vol. 17, 1894, 

 p. 53. 



Diagnosis. — Rostrum terminating in a slender spine; in addition, 

 three median spines on carapace. Chelipeds slender. 



Description. — Carapace slightly pubescent; unevenly granulate 

 with unequal granules, the largest ones on the summit of the branchial 

 regions, which have the greatest number of granules; a few small 

 granules on cardiac and gastric regions; more on the hepatic regions; 

 lateral and posterior margins covered with small granules. Four 

 median capitate spines, one at end of rostrum, one gastric, one 

 cardiac, and one directed obliquely backward and upward on the 

 first abdominal segment. In young specimens the rostral spine is 

 bifid at tip; and this bifurcation sometimes persists in older speci- 



\^ 



Fig. 35.— Collodes TENUIROSTRIS, MALE (21867), X 8. a. Left chela, b. Rostrum 



mens up to 12 mm. in carapace length. A supraorbital tubercle; a 

 rather broad postorbital lobe directed obliquely forward. Basal 

 antennal segment with a prominent inner lamina ending in a lobe 

 and an outer margin cut into numerous denticles. The male sternum 

 is granulate on the cheliped segment near the abdomen and especially 

 on the most protuberant parts; granules few on other segments 

 except close to abdominal cavity. Female abdomen roughened 

 with numerous but separated granules. 



Chelipeds slender; outer margin of merus armed with about 

 eight stout spinules, other margins finely spinulous, as is also the 

 inner margin of the carpus; manus nearly smooth; fingers narrowly 

 gaping in basal half. Legs long-hairy, the hairs retaining large 

 quantities of mud. 



Measurements. — Male (21867), length of carapace 18.8, width 

 14.7, length of cheliped 20.6, of first ambulator}^ leg 35.7 mm. 

 Female (21867), length of carapace 17, width 13.4 mm. 



Range. — West coast of Lower California and Gulf of California. 

 Depth, 36 to 145 fathoms. 



Material examined. — See table, page 111. 



