THE CANCROID CRABS OF .\]VIERICA 59 



narrower than the allied species and the antero-lateral border more 

 arched. The branchial ridge runs obliquely forward from the lateral 

 spine,- then turns rather abruptly inward in an almost transverse 

 direction, the line being a little concave forward. Frontal teeth 

 small, triangular mth blunt points, those of outer pair not much 

 the larger, wider at base than those of the inner pair, and not quite 

 so advanced. The second, fourth, and sixth lateral teeth are some- 

 what reduced. The lateral spine is about as long as the width of the 

 next 2)4 or 3 teeth, and curves a little forward. The margin of the 

 carapace at the obtuse latero-posterior angles has a tendency to form 

 a raised rim. Chelipeds very long, more than 3 times as long as 

 carapace in male, more than 2}^ times in female. Merus little en- 

 larged, armed normally with 4 spaced spines (occasionally a fifth 

 small one) on the anterior margin, and one very small spine at ex- 

 tremity of outer margin. Inner spine of wrist about twice as long as 

 proximal spine of palm; outer spine of wrist much smaller than 

 either. The male abdomen resembles that of acuminatus. 



In this species the outer tooth of the orbit (first antero-lateral 

 tooth) is wider than in asper, having a more decided angle on its outer 

 margin; the intramedial area (that part of the gastric region behind 

 the posterior of the gastric carinae) is shorter and broader than in 

 asper, the intermediate of the gastric ridges is formed by a narrow 

 irregular row of coarse granules instead of the band of coarse granules 

 in asper. 



Measurements. — Male (22023), total length of carapace 22.5, 

 width of same 45, width from base of lateral spines 35.4, fronto- 

 orbital width 17.7, width of front 5.6 mm. 



Range. — From east and west coasts of Lower California, Mexico, 

 to Peru. Chile (A. Milne Edwards). 



Material examined. — 



PANAMA.— Panama Bay; March 5, 1888; Albatross: Lat. 8° 10' 

 30" N., long. 78° 50' 30" W.; 18 fathoms; gy. S. brk. Sh.; station 

 2798; 1 female (22024). Lat. 8° 06' 30" N., long. 78° 51' 00" W.; 

 33 fathoms; gy. S. brk. Sh. ; station 2797; 32 males, 11 females 

 (22023, 25429). 



Taboga Island; June, 1924; Elizabeth Deichmann; 1 male, 1 

 ovigerous female (61316). 



Panama; March 15, 1860; A. Agassiz; 1 male (5271, M.C.Z.). 



PERU.— Paita; October 7, 1926; W. L. Schmitt; 1 young (62486). 



Bay of Sechura, W. of Matacaballa; 1907; R. E. Coker; gift of 

 Peruvian Government: About 5 fathoms; April 8; 2 females (40440). 

 5-6 fathoms; April 10; 1 male (40439). 



