47° Records of the Indian Museum. [Vox,. XXIV, 



gins with about ten spines distributed throughout their length, more 

 distantly placed proximally, nearer together distally, the most dis- 

 tal marginal spine less than half as long as the outer spines of the 

 apex ; no plumose setae at the centre of the apex. 



Inner uropod half as long again as the telson, with a comb of 

 ten spines on the lower surface in the region of the statocyst but 

 not extending down the inner margin. 



Outer uropod nearly twice as long as the telson. 



Fourth pleopod of the male of the usual, type found in My- 

 sidopsis, both rami six-jointed, the outer ramus longer than the 

 inner and terminating in a single, long, stout plumose spine. 



Remarks. — This species is a very typical member of the genus 

 Mysidopsis but is easily distinguished from all the other species by 

 the shape and armature of the telson. 



Genus Leptomysis G. O. Sars. 

 Leptomysis xenops, sp. nov. 

 Text-figs, i^a-g. 

 Leptomysis apiops'!, Zimmer, 1915 (3), p, 167, fig. 19. 

 Locality. — Port Blair, Andaman Islands. 

 St. 5. Two. 

 St. 11. Abundant. (Types.) 



Description. — Agreeing with Leptomysis apiops G. O. Sars, 

 except in the form of the telson. The latter is linguiform in shape, 

 one and a half times as long as broad at the base ; apex more or less 

 truncate, half as long as the width of the telson at the base, 

 armed with three pairs of stout spines, the innermost pair the 

 longest, equal in length to two-fifths of the length of the telson ; 

 between the inner pair of spines are two small spinules about one 

 quarter of the length of the spines ; the spines immediately out- 

 side the inner pair are about two-thirds of the length of the latter 

 and the outer spines of the apex are slightly less than one half 

 of the length of the inner pair ; the lateral margins of the telson 

 bear a single long spine at the point of the greatest width of the 

 telson and from 14-17 spines on the rest of the margin, the prox- 

 imal ones more distantly placed than the distal, the spines increas- 

 ing in size in regular sequence towards the apex and not arranged 

 in groups. 



For the rest of the characters reference may be made to Sars' 

 figures of L. apiops with which this species agrees in all its other 

 characters. I have given figures of the principal appendages of L. 

 xenops for comparison. 



Zimmer (19 15 (2) ) has given a new figure of the eye of L. apiops 

 to illustrate the elongation of certain facets which leads to the 

 peculiar shape of the eye, from which the species takes its name. 

 The present species has eyes of exactly the same form. In fact it 

 is very closely allied to L. apiops , but the latter has about 35 



