434 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



and armed with a stout tooth near the middle of the prehensile edge. 

 The dactylus is as long as the basal portion of the propodus, about three- 

 fourths longer than the propodal digit, strongly curved toward the tip, 

 and the prehensile edge is sharp and minutely crenulate, but not toothed, 

 and closes by the inner side of the tip of the propodus. The smaller 

 cheliped is similar in form to the larger, but is considerably shorter and 

 very much more slender, and the propodal digit is proportionately longer 

 and its prehensile edge thin and minutely multidentate. Both cUelce 

 are sparsely hairy on the digits and very slightly along the margins of 

 the basal i)ortions. The second pair of legs are very slender and a little 

 longer than the carapax; the merus is about as long as the carpus and 

 chela taken together; the carjous is less than half as long as and slightly 

 narrower than the merus and about three times as long as broad; the 

 chela is slightly longer but scarcely broader than the carpus, and the 

 digits are slender, longitudinal, not gaping, and a little shorter than the 

 basal portion. The third and fourth jiairs of legs are very nearly alike, 

 and as long as the second, but more slender ; the merus is about as long 

 as the carpus and propodus together; the propodus is about a third 

 longer than the cari)us; and the dactylus is slender, nearlj^ straight, and 

 about two-fifths as long as the propodus. The fifth, or iiosterior, legs 

 are considerably shorter and much more slender than the third and 

 fourth pairs, being nearly cylindrical; the merus is about as long as the 

 propodus; the carpus about three-fifths as long; the dactylus is about 

 half as long as the carpus. 



The abdomen is much narrower than the carapax and not expanded 

 in the middle, the sides being nearly straight and i^arallel. The lamellaj 

 of the nropods are about as long as the telson, the outer as long as 

 broad, the inner a little narrower. The telson is about a third longer 

 than the sixth somite of the abdomen, about two-thirds as broad as 

 long; the lateral edges are nearly parallel and each armed with about 

 four small spines; the posterior margin is regularly arcuate. Near the 

 middle of the dorsal surface there is a transverse line of four small spines, 

 and there are one or two more between these and the tip. 



An imperfect male specimen, wanting the chelipeds and most of the 

 abdomen, lias three spines in front on the dorsal carina, and the spines, 

 of the rostrum slightly longer than in the female. 



The single female gives the following: 



mm. 



Length from tip of rostrum to tip of telson 44. 



Length of carapax to tqi of rostrum 16.3 



Length of rostrum 3.1 



Height of carapax 8. 2 



Breadth of carapax 7. 



Length of right cheliped 31.0 



Length of k-ft cheliped 25.0 



Length of right merus 8. 3 



Length of left merus 7.0 



Length of right jnopodus 12.5 



