THE SPIDER CRABS OF AMERICA 157 



nearly transverse (in the full growTi); on the anterior margin near 

 its middle there is a lobe or tooth, very small in the half grown but 

 increasing until it equals the tooth at the antero-lateral angle of the 

 lobe. Branchial lobe triangular, acute or subacute. Preorbital 

 tooth distinct, outstanding, tuberculiform ; postorbital tooth incon- 

 spicuous, not projecting beyond carapace margin and indicated only 

 by a closed fissure. Rostrum broadly oblong, sides subparallel, 

 extremity bilobed, median sinus broad, shallow. (Fig. 53, m, n.) 



Chelipeds of moderate size; merus very bluntly angled; carpus 

 and manus with a subacute, outer carina; a tubercle on upper sur- 

 face of carpus; manus elongate, not widening much until just before 

 the fingers, which are short, very wide, deflexed, outer margin 

 acutely carinate, gape narrow, a large tooth on the dactyl within the 

 gape. Ambulatory legs rather stout; two tubercles on lower margin 

 of proximal half of merus of first leg; propodites mthout tooth or 

 tufts of hair. Third, fourth, and fifth segments of male abdomen 

 fused. 



Measurements. — Male (Laguna Beach), median length 16.1, ante- 

 rior width 14.5, posterior width 15 mm. Male holotype (50599), 

 median length 13.6, total length 14, anterior width 12.2, posterior 

 width 12.4 mm. 



/?an^e.— California: Laguna Beach and Santa Catalina Island. 



Material examined. — Laguna Beach, Orange County; William A. 

 Hilton, Pomona College; 1 male, holotype 

 (50599), 1 male returned to sender. 



Catalina Harbor, Santa Catalina Is- 

 land; W. H. Dall; 1 male (18136). 



EPIALTUS PERUVIANUS Rathbun 



Epialtus peruvianus Rathbun, Proc. Biol. 

 Soc. Washington, vol. 36, 1923, p. 72 

 (type-locality, Chincha Islands, Peru; 

 holotype, Cat. No. 54208, U.S.N.M.). 



Diagnosis. — A tooth at base of pro- fig. ss.-efultus peruvianas, male 



T, . » 1 1 i • /-( (54208), LOOSE LEG. The CARAPACE IS 



podites of ambulatories. Carapace very ^ g j^^ ^ong 

 uneven. Hepatic lobe large, branchial 

 small. Rostrum oblong, bilobed (fig. 53, i). 



Description of maZe.— Median region separated from hepatic and 

 branchial regions by a deep furrow; a transverse, depressed area 

 across the carapace embraces anterior edge of hepatic lobes; a sharp, 

 median, interorbital sulcus. Hepatic lobe very large, recurved, 

 anterior margin transversely concave, outer angle lobiform, promi- 

 nent, posterior margin slightly convex; branchial lobe very small, 

 acute, sides concave. Orbital arch swollen, margin forming an angle, 

 not a tooth, with the margin of the rostrum. Rostrum deflexed^ 



