jgi^.j S. Kemp : Notes on Crustacea Decapoda. 103 



The last abdominal somite is about twice the length of 

 the fifth. The telson bears two pairs of dorsal spinules and 

 terminates in a narrow pointed process flanked by a pair of 

 spines on either side. The innermost of these is more than 

 twice the length of the outer and is often nearly twice as long 

 as the median process. The outer uropod is shorter than the 

 inner and is about three and a half times as long as broad. 



In the male the whole form of the animal is far more slender, 

 as will be seen on comparing figs. 1 and 2, plate IV. The 

 rostrum is longer and much narrower in lateral view; it extends 

 well beyond the apex of the antennal scale and exhibits the follow- 

 ing spine formulae — 



1)7 1)7 1)7 1)8 1)5 £)5 



1)4 i]4 1)5 J06 _2)5_ 



X ~^ 4 I o 



It seems that, as in L. pygniaeus, the teeth are on the whole 

 less well-developed in males than in females ; some of the males ^ 

 however, are of very small size and may not have developed the 

 full complement. Seen laterally the greatest length of the rostrum 

 from the back of the orbit to the apex varies from two and a half 

 to four times its greatest height: proportions strikingly variable 

 and different from those found in the female {cf. pi. Ill, figs. 10, 

 II, pi. IV, fig. 2, and pi III, figs. 8, 9, pi. IV, fig. i). 



The carapace is not arched in lateral view. It bears a single 

 dorsal fixed spine in ten of the specimens examined, while in the 

 eleventh, which in this respect resembles the type of L. gravieri, 

 there are two. It will be noticed that one, three, or four spines 

 have been found in this situation in females. 



The differences in other respects between the two sexes are 

 less striking. There may be only six or seven spines on the antero- 

 lateral margin of the carapace. The upper antennular ramus is 

 stouter and very considerably longer than in the female ; this 

 feature affording the readiest distinction between the two sexes. 

 The antennal scale may be four and a half times as long as broad 

 ui young males (pi. Ill, fig. 14); in older specimens the length is 

 usually about three and a half times the breadth. In one 

 individual the outer margin is very definitely concave (pi. Ill, 



fig- 15)- 



The third maxillipede scarcely reaches beyond the antennular 

 peduncle. The second peraeopods in large specimens reach 

 beyond the middle of the antennal scale, but are shorter in small 

 examples. They agree precisely with those of the female in the 

 proportional length of the segments. 



The dactylus of the last three pairs agrees with that of the 

 female and is a little more than one third the length of the 

 propodus The propodus of the fifth leg is usually shorter than in 

 the female and is not quite so long as the merus. 



