PINNOTHERHXE 55 



Raphonotus subquadratus (Dana). 



Fabia subquadratus Dana, Proc. Acad. Nat. Sci. Phila., 253, 1851. Holmes, Occas. 



Papers Calif. Acad. Sci., vii, 87, 1900, and synonymy (part). 

 Raphonotus subquadratus Rathbun, H. A. E., x, 186, 1904. 



Numerous specimens of Raphonotus from Monterey Bay agree with 

 Miss Rathbun's description of the portion retained as typical subquad- 

 ratus, in distinction to R. lowei, in having a distally widened hand with 

 two rows of hair on the lower margin although they do not all show 

 pubescence of the frontal region. The females are very common in the 

 mantle cavity of the mussel (Mytilus edulis) Miss Rathbun reports it 

 also from folds of Lucapina crenulata but I have seen no males. 



Genus PINNIXA White. 



Pmnixa White, Ann. Mag. Nat. Hist., xviii, 177, 1846 (Type Pinnixa cylindrica 

 Say). 



The genus Pinnixa is well represented on the Pacific Coast but the 

 material at hand is scanty. The following key to the species taken in 

 part from Miss Rathbun and Holmes is not intended to apply to extra- 

 limital forms. I have examined all of the six species. 



KEY TO SPECIES OF PINNIXA FOUND IN MONTEREY BAY. 



a. Dactyl of third pair of ambulatory legs straight. 



b. Carapace about i l / 2 times as wide as long. P. faba 



bb. Carapace twice or more than twice as wide as long. 



c. Propodus of third pair of ambulatory legs largest at distal 

 end, markedly wider than base of dactyl; pollux of 

 cheliped not markedly shorter than dactyl and not bent 

 downward. P. tubicola 



cc. Propodus of third pair of ambulatory legs largest near the 

 proximal end, tapering to base of dactyl; pollux of 

 cheliped shorter than dactyl and bent downward at an 

 angle to the palm. 



d. Carapace about twice as wide as long, areolations well 

 marked. P. occidentalis 



dd. Carapace rather more than twice as wide as long, areo- 

 lations less prominent. P. californiensis 



