THE SPIDER CRABS OF AMERICA 27 



The carpus of the chelipeds has four spines, three small ones in a 

 diagonal row near the inner margin and a larger spine near the anterior 

 outer angle. The manus is less elongate than in furcillatus and of 

 more nearly uniform width throughout. Fingers of male more 

 gaping than in male oi furcillatus and with a large basal tooth. 



Ambulatory legs shorter than in furcillatus, the last two articles of 

 the third leg less falcate. Fourth leg not much longer than third, 

 but less falcate, as is the case in the related species. No spines on 

 lower surface of merus of third leg. Longer spinules on lower border 

 of last two pairs of dactj^ls. 



Measureinents. — Male (15157), length of carapace including rostrum 

 13, rostrum 6, width of carapace 4.8, length of cheliped 15.4, first leg 

 28.3, second leg 20.5, third leg 10.5, fourth leg 14.2 mm. 



Range.— O^ Havana; Montserrat; Guadeloupe; Dominica; Bar- 

 bados. Depth, 73 to 183 fathoms. 



Material examined. — See table, page 28. 



Genus ACHAEOPSIS Stimpson 



Achaeopsis Stimpson, Proc. Acad. Nat. Sci. Philadelphia, vol. 9, 1857, p. 



219 [251; type, A. spinulosus Stimpson; Smithson. Misc. Coll., vol. 49, 



1907, p. 21. 

 Dorynchus Norman, in Wyville-Thomson's Depths of the Sea, 1873, p. 175; 



type, D. thomsoni Norman. — Rathbun, Proc. Biol. Soc. Washington, 



vol. 11, 1897, p. 162. 

 Lispognalhus A. Milne Edwards, Crust. Reg. Mex., 1880, p. 349; type, L. 



furcillatus A. Milne Edwards, 1880= A. thomsoni (Norman, 1873); Bull. 



Mas. Comp. ZooL, vol 8, Dec. 28, 1880, p. 8. 



Carapace ovate-triangular, convex, spinous; interorbital portion 

 narrow; a supraorbital and a postorbital spine. Rostrum usually 

 bifid, not very long. Eyes retractile to sides of carapace. Antennular 

 fossae long and narrow. Basal article of antennae very long and 

 narrow and placed almost in a vertical plane; movable portion much 

 longer thaii the rostrum and inserted beside it. Outer maxillipeds 

 spinous; merus narrower than ischium, constricted at base, rounded 

 at extremity, palpus articulating at summit. Abdomen composed of 

 six segments in both sexes. Chelipeds strong, spinous; merus 

 trigonal; manus dilated; fingers broad. Ambulatory legs long and 

 very slender. 



Contains several species of which only one, which has a very wide 

 range, inhabits American waters. 



