THE SPIDER CRABS OF AMERICA 293 



Basal segment of antenna with outer margin convex, a stout spine 

 at antero-lateral angle, directed forward; flagellum surpassing ros- 

 trum. Epistome sharply recessed at middle. 



Chelipeds weak in both sexes, much shorter than next leg; merus 

 cylindrical, very rough; carpus granulate; palms smooth, tapering to 

 the fingers, which are one-fifth as long as upper margin of palm. 

 Ambulatory legs stout, somewhat angled, armed with two longi- 

 tudinal rows of spines and rough with two sorts of tubercles; dactyls 

 finely roughened, tips horny. 



Measurements. — Male holotype, length of carapace 17, width 9 mm. 



Range. — Known only from the type-specimens, off Arrowsmith 

 Bank, Yucatan; lat. 20° 59' 30" N.; long. 86° 23' 45" W.; 130 

 fathoms; Co.; January 22, 1885; station 2354, Albatross; 2 males, 

 6 females (9546). 



Genus HERBSTIA Milne Edwards 



Herbstia Milne Edwards, Hist. Nat. Crust., vol. 1, 1834, p. 301; type, 



H. condyliata (Fabricius). Name not invalidated by Herbstium Leach, 



1823. 

 Rhodia Bell, Proc. Zool. Soc. London, vol. 3, 1835, p. 169; type, R. pyriformis 



Bell. 

 Herbstiella Stimpson, Ann. Lye. Nat. Hist. N. Y., vol. 10, 1871, p. 93; type, 



H. depressa Stimpson. 

 Fisheria Lockington, Proc. California Acad. Sci., vol. 7, 1876 (1877), p. 72 



[10]; type, F. depressa Lockington = Herbstia camptacantha (Stimpson), not 



H. depressa (Stimpson). 



Carapace broadly triangular or subpyriform, tuberculated or 

 spinose. Rostrum short, horns acute, vertically compressed and 

 dilated at base. Orbits complete, shallow, with or without a pre- 

 orbital spine. Eyes short, not entirely concealed when retracted. 

 Basal antennal article moderately dilated and armed with an antero- 

 external spine, the distal portion not entirely covered by the rostrum. 

 Merus of maxillipeds distally truncated and not produced at outer 

 angle. Ambulatory legs rather slender, subcylindrical and of mod- 

 erate length; dactyls nearly straight, acute. 



East and west coasts of tropical America; Mediterranean and south- 

 ward along the west coast of Africa. 



KEY TO THE AMERICAN SPECIES OF THE GENUS HERBSTIA 



A'. Merus of ambulatory legs armed with spines. 

 B*. Two teeth on outer margin of basal antennal article behind antero-external 

 tooth or spine. 

 C. First movable article of antenna falling considerably short of tip of 

 rostrum; postocular tooth small, directed forward. 



camptacantha, p. 294. 

 C^. First movable article of antenna nearly as advanced as tip of rostrum; 



postocular tooth large, directed obliquely outward depressa, p. 298. 



B'. One tooth on outer margin of basal antennal article behind antero-external 

 tooth or spine. 



