LEPTOSTRACA, SCHIZOPODA AND STOMATOPODA. 165 



The outer uropod is a little longer than the inner and much broader, the terminal 

 joint being about one quarter of the length of the proximal one, the latter armed on 

 the distal two thirds of its outer margin with 15 strong spines increasing in length 

 posteriorly. 



Length of an ovieerous female 12 millims. 



The above description is based on the single Ceylon specimen in this collection, 

 which I refer to this species. The male is as yet unknown. Professor Paulson" 

 (1875) first described this species, though he referred his specimens at the time 

 to S. jaltensis, < zerniavsky. Kossmann (1880), who had a much larger specimen 

 of what be believed to be Paulson's species at his disposal, recognised that it differed 

 rather markedly from S. jaltensis, and, therefore, re-described it, with figures, under 

 the name S. paulsoni. Czerniavsky (1880) likewise came to the conclusion that 

 S. jaltensis, Paulson, was not the same as his species, and, apparently unacquainted 

 with Kossmann's earlier paper, fortunately also re-named it S. paulsoni. He had, 

 however, no specimens, and drew up his diagnosis entirely from Paulson's work. 



Though both Czerniavsky's and Kossmann's descriptions are imperfect in many 

 points, they only differ in one important detail from the Ceylon example, namely, in 

 the number of spines on the outer margin of the first joint of the outer uropod. 

 ( 'zerniavsky gives the number as seven, Kossmann figures eight, while the Ceylon 

 specimen has fifteen. This great difference may, I think, be explained by the 

 difference in size of the individuals from which the various descriptions were drawn 

 up. Czerniavsky's description was based on Paulson's specimen, 4 millims. in 

 length; Kossmann's example was 8 "5 millims., while the Ceylon one is 12 millims. 

 The spinulation of the telson and uropods is known in other species of the group 

 to vary with the size of specimens. In all other respects the present example 

 agrees in the main with Kossmann's figures. S. paulsoni approaches nearest to 

 ,S'. ffcnticiilnta, G. M. Thompson, among all the species of Siriella which have been 

 described, but differs from the latter (1) in the length and proportion of the joints 

 of the antennal peduncle ; (2) in the deviating form of the antennal scale; (3) in the 

 presence of spines on the lateral margins of the telson above the constriction ; (4) in 

 the much larger number of spines on the inner uropod. From the three Pacific 

 species of the genus S. gracilis, S. thompsoni and S. indica S. paulsoni may be 

 at once distinguished by having the outer uropod longer than the inner, and in having 

 many more spines on the outer edge of the former. Previous to Professor Herdman's 

 capture of this species in Ceylon it was only known from the Red Sea. Its 

 geographical distribution has thus been considerably extended. As far as I am 

 aware, it is the first Mysid ever recorded from Ceylon. 



Haplostylus erythraeus, Kossmann (?). 



Locality : South end of Red Sea, surface tow-net. One female, 5 millims. 



In consequence of its small size and damaged condition the absolute identity of 



