90 CALIFORNIA ACADEMY OF SCIENCES. 



Described from specimens received from Miss Rath- 

 bun. 



Alaska to Washington, San Diego (Rathbun); British 

 Columbia (Newcombe). 



In the female the carapace is more tumid and the 

 chelipeds smaller. One small female which I collected 

 on the coast of Humboldt County, Calif., had the cara- 

 pace entirely covered with a short pubescence. 



Pinnixa californiensis Rath. 



Pinnixa californiensis RATHBUN M., Proc. U. S. Nat. Mus., Vol. XVI, 1893, 

 p. 249; and Vol. XXI, 1898, p. 605. 



This species is very closely allied to occidentalis, but the carapace is 

 relatively wider and more flattened above, the cardiac ridge does not curve 

 backwards so strongly in the middle, the antero-lateral ridge is straighter, 

 and curves backward more abruptly toward the outer end, the median 

 region is less tumid, and the carapace descends more abruptly at the sides. 

 The second abdominal segments in the males of the two species that I 

 have do not present any appreciable differences, although in the specimens 

 described by Miss Rathbun the sides of that segment were parallel in 

 californiensis and divergent posteriorly in occidentalis. The ambulatory 

 legs are almost exactly alike in the two species and differ much from those 

 of the other Pinnixas on our coast. 



Length of Carapace. Breadth of Carapace. Length of Third 



Ambulatory Leg. 



Male 4.75 mm 10 mm 13 mm. 



Female 4.5 mm 9.75mm 12mm. 



Described from specimens received from Miss Rath- 

 bun. 



Monterey Bay and off Point Ano Nuevo, California; 

 Magdalena Bay, Lower California (Rathbun). The 

 locality of the specimens described is lat. 36 47' 50" N.; 

 Ion. 121 49" W.; depth, 37 fathoms. 



