THE SPIDER CRABS OF AMERICA 89 



Abdomen composed of seven free segments in both sexes; in the male 

 constricted at fifth segment; sixth segment with convex lateral out- 

 lines; seventh rounded, broader than long. Chelipeds small, smooth, 

 and shining; raerus subtrigonal; carpus with a tubercle above, near 

 merus; hands compressed, margins converging toward fingers. Ambu- 

 latory legs subcylindrical; dact^di very slender and much curved. 

 Carapace and ambulatory legs clothed with hair. 



Measurements. — Male, holotype, median length of carapace 4.4, 

 length to tip of horns 4.7, width of carapace 3.3 mm. Female 

 (19405), median length of carapace 5.9, length to tip of horns 6.3, 

 width of carapace 5 mm. 



Range. — Bahama Banks; West Indies. 



Material examined. — 



Bahama Banks; 1893; State Univ. Iowa Exped. (specimen in 

 S. U. I.). 



Port Royal, Jamaica; P. W. Jarvis; 1 male (holotype), 2 ovigerous 

 females (19405). 



Arroyo, Porto Rico; February 4, 1899; Fish HawJc; 1 young female 

 (24219). 



Genus ARACHNOPSIS Stimpson 



Arachnopsis Stimpson, Bull. Mus. Comp. ZooL, vol. 2, 1S71, p. 121; type, 

 A.filipes Stimpson. — A. Milne Edwards, Crust. Reg. Mex., 1878, p. 181. 



Carapace oblong, narrow, and somewhat truncated in front. 

 Rostrum short, bifid. Orbital arch high, protuberant. Postocular 

 lobe long, separated from the orbital arch by a deep, narrow fissure. 

 Eye long, considerably overreaching the tip of the postocular lobe, 

 but capable of being drawn back beneath it. Basal article of anten- 

 nae with two spinulous crests on the inferior surface which meet 

 anteriorly, the outer crest continued back to the angle of the buccal 

 area; a small, sharp spine at extremity, pointing obliquely forward 

 and outward, between which and the rostrum the long movable part 

 of the antenna is exposed. Merus of maxillipeds broader than long, 

 and with sharply prominent internal and antero-external margins. 

 Ambulatory legs long, filiform, second pair longest; dactyls slightly 

 curved, nearl}" as long as the penult article. The last three segments 

 of the abdomen are coalesced in the female. 



Contains only one species. 



ARACHNOPSIS FILIPES Stimpson 



Plate 32, figs. 1 and 2; plate 219, figs. 4 and 5 



Arachnopsis filipes Stimpson, Bull. Mus. Comp. ZooL, vol. 2, 1871, p. 121 

 (type-localities, off Conch, Carysfort and French Reefs, Florida, 34 to 45 

 fathoms; types not extant). — A. Milne Edwards, Crust. R6g. Mex., 

 1878, p. 181; 1879, pi. 33, figs. 1-lc; Bull. Mus. Comp. ZooL, voL 8, 1880, 

 p. 6.— Kendall, Bull. U. S. Fish Comm., vol. 9, for 1889 (1891), p. 303.— 

 Rathbxjn, Proc. U. S. Nat. Mus., vol. 17, 1894, p. 57; Bull. Lab. Nat. 



