THE GEAPSOID CRABS OP AMEEICA. 69 



Diagnosis. — Carapace of female soft, broadest behind, gastric re- 

 gion defined. Manus widest a little way behind fingers. Leg 1 stout, 

 widest distal to middle; legs 2, 3, and 4 very slender and diminishing 

 in order named. 



Description of female. — Carapace very soft and yielding, broader 

 than long, the front and long antero-lateral margins forming a single 

 arch; posterolateral margins short, oblique, concave; posterior mar- 

 gin long, concave; greatest width in posterior half; carapace convex, 

 thick, rounding gradually downward, except posteriorly; gastric 

 region defined by a depression, which is deeper and narrower than 

 in ostreum^ and suggests that in Fabia. Front between orbits trun- 

 cate, medially faintly emarginate, orbits partly visible from above. 



Carpus of outer maxilliped suboblong; propodus no longer than 

 carpus, and narrower, end obliquely rounded; dactylus linear, of 

 nearly even w^idth throughout, rounded at extremity, inserted near 

 proximal end of propodus and not reaching its distal end. 



Chelipeds stouter than legs, but not very large; lower margin of 

 propodus nearly straight, palmar por- 

 tion widening rapidly to a point be- 

 hind base of fingers; fingers stout, 

 hooked at tips, prehensile edges un- 

 even, an acute tooth near base of 

 dactyl. 



Relative length of legs represented 

 by 2.3.1.4, the second longest; 2, 3, fig. "^T— pinnotheres holmesi, 

 and 4 very slender; dactyl 2 much outer maxilliped of female 

 longer than 3 or 4 and curved on holotype, 

 both margins, dactyl 3 less curved on anterior and nearly straight 

 on posterior margin, dactyl 4 a trifle longer than 3, margins nearly 

 straight; horny tips of all four very slender and hooked. First leg 

 stout, especially propodus, not reaching middle of propodus of sec- 

 ond; propodus widest distal to the middle and narrowest at distal 

 extremity; dactyl shortest of all, conical except for tip. 



Abdomen voluminous, much longer and wider than carapace. 



Measurements. — Female holotype, length of carapace 7.2, w^idth of 

 same 8.7 mm. 



Range. — Known only from the type-locality, which is probably 

 Pacific Grove, California. 



Affinity. — In shape resembles P. ostreum of the Atlantic coast, 

 which has also a similarly enlarged propodus of first leg; first 3 

 legs of holmesi much slenderer than of ostreum. 



