iQoS.] Records of the Indian Museum. 235 



Eyes reaching to about the distal extremity of the basal joint 

 of the antennular peduncle ; rather stout ; cornea occupying the 

 entire distal part of the eye, pigment very black. 



Mouth parts of the usual type in the My since ^ with no out- 

 standing feature of importance. 



Thoracic legs (figs. 4, 5, 6) ; first and second without a distinct 

 dactylus ; third to eighth with the tarsus equal in length to the 

 merus and three jointed in all but the eighth, where it is four 

 jointed. 



Telson (fig. 7) about two-thirds of the length of the last seg- 

 ment of the pleon, and rather longer than broad at its base ; apex 

 truncate and bounded at each corner by a long spine between 

 which are about seventeen shorter spines ; lateral margins armed 

 throughout their length with about ten short spines. 



Inner uropod about twice as long as the telson; no spines on 

 the inner ventral margin. 



Outer uropod about one-and-a-quarter times as long as the 

 inner. 



Length of an adult female with eggs in the broad lamellae, 

 5 mm. ; length of the largest male, apparently mature, 4 mm. 



The above description and fig. I, pi. xxi, are taken from an 

 adult female, 5 mm. long. The figures of the various parts are 

 from a male measuring 4 mm. in total length, and this differ- 

 ence in size probably accounts for the difference in armature of 

 the telson as shown in fig. 7 and that given in the above descrip- 

 tion. A still smaller specimen, 3 mm. in length, had only seven 

 spines on the apex of the telson between the two large lateral ones. 

 Czerniavsky has shown similar differences between young and adult 

 specimens of P. pengoi. 



A male of 4 mm. appears, to judge by the fourth pleopods, 

 to be mature if not fully grown. The fourth pleopod of such a 

 male is shown in fig. 8. The basal joint is short and the inner 

 ramus of the usual structure. The outer ramus is long and styli- 

 form, reaching to the posterior end of the sixth segment of the 

 pleon. It is three jointed, the second the shortest and the ter- 

 minal joint the longest. The latter is furnished at its apex with two 

 long, subequal ciliated filaments and on the outer distal margin 

 with a single smooth filament, longer than the ciliated filaments at 

 its apex. There is no prominent hirsute lobe on the antennules 

 of the above male specimen, such as is usually met with in male 

 Mysidse. It is replaced by a tuft of long hairs proceeding from 

 a small tubercle on the distal ventral edge of the antennular 

 peduncle. 



Locality of capture. — Dhappa, near Calcutta, slightly brackish 

 water (canal), six females and three males. 



This species differs from P. pengoi in the following points : — 

 (i) Size. — The type-specimen of P. pengoi was an adult 

 female measuring to mm. Adult females of the pres- 

 ent species with eggs in the brood-pouch only mea- 

 sure 5 mm. 



