22 PROCEEDINGS! OF THE NATIONAL MU8EVAL vol. xxxvi. 



longer than the median; the stylocerite usually reaches the distal 

 third of the median antenniilar article, but ahvays to at least the 

 middle of the article. 



The lateral spine of the basicerite is as long as the rostrum; the 

 lateral spine of the scaphocerite is very slightly shorter than the 

 carpocerite, which is short, beginning at the distal third of the basal 

 antennular article, three times as long as wide, the margins almost 

 parallel, excepting at the base, where it is slightly swollen ; it ex- 

 ceeds the antennule by one-half the length of the distal article ; the 

 outer maxillipeds exceed the antennule by about one-half of its 

 length. 



The anterior margin of the palm of the large chela terminates in 

 a conical tubercle, short and always destitute of a spine, as Locking- 

 ton distinctly says. I found the proportions of the chela to be: 

 Finger 1; total length 3; height 1.1; proportion T. L. : H.='2.9: 1. 

 The anterior margin of the meropodite terminates in a triangular 

 point. 



The proportions of the small chela are : Fingers 1 ; total length 

 2.36; height 0.84; proportion T. L.:H. =2.8:1. The carpus is not 

 spinous on its superior margin ; the meropodite terminates on this 

 margin in a triangular point, its thickness being a little less than 

 that of the palm, contained 1.9 times in its length. 



In the second pair the first segment of the carpus is slightly 

 shorter than the sum of the four following ones; the meropodite is 

 shorter than the carpus. 



The mero^wdite of the third pair is approximately equal to the 

 carpus of the second pair, and 3.75 times longer than wide. The 

 proportions of the members are : Carpus 1 ; propodite 2 ; meropodite 

 2.15; the dactyl is very slender, the dorsal hook twice as long as the 

 ventral. 



The posterior angles of the telson are right angles, not prolonged 

 to a triangular prominence. 



Named for Mr. W. N. Lockington, the original describer of the 

 species. 



The description by Lockington — very explicit as to the length of 

 the antennal spines, the form of the chela of the first pair, the 

 carpus of the second pair, the dactyl of the third pair, and the 

 telson — appears to permit identification of the specimens of /S. 

 levluscultis with those which I have studied. The differences bear 

 upon two points: Lockington says that the spine of the scaphocerite 

 does not reach the extremity of the peduncle and that the movable 

 finger of the large chela projects beyond the pollex. The first 

 character hardly exists on the specimens that T have seen, the spine 

 being approximately equal to the carpocerite and the fingers of the 

 large chela equal. 



