1915O Fauna of the Chilka Lake : Mysidacea. 153 



somewhat distantly placed spines on its inner margin , the proximal one of which is on 

 the statocyst. 



Large epimeral plate of the first segment of the pleon in the female with its 

 front margin microscopically serrulate. 



Tarsi of the third to the eighth thoracic limbs composed of from seven joints in 

 the third pair to eleven joints in the eighth pair. Basal joint of the exopodites of 

 all the thoracic limbs with a prominent tooth at its outer distal corner, except in the 

 eighth pair where this corner is rounded. 



Pleopods of the female very similar to those in G. spinifer except that the two 

 branches of the first pair are more nearly equal in size than shown in Stebbing's 

 figure (1880). 



First, second, fourth and fifth pleopods of the male agreeing closely with those 

 figured by Sars (1877) for G. sanctus. With the exception that the exopod of the first 

 pair is eight-jointed, both the exopod and the endopod of the second pair are eight- 

 jointed, and the endopod of the fourth and fifth pairs is seven-jointed, Sars' figures 

 would serve very well to illustrate the present species. The agreement in the general 

 form and proportions is of the closest character. 



The third pleopods of the male differ vastly from those of the male of G. sanctus. 

 The endopod is similar to that of the preceding and succeeding pairs, seven-jointed, 

 and extending about half way down the second joint of the exopod. The exopod is 

 very elongate, reaching to the base of the telson and divided into five joints. The 

 first joint shows three suture lines representing subsidiary joints, similar to those 

 shown in Sars' figure (1877) of the same appendage of G. sanctus. The second joint 

 is shorter than the first, and the third joint is as long as the first and second com- 

 bined but more slender. The fourth joint is short and has the distal lower margin 

 produced into an obtuse lobe. The terminal joint is longer than the fourth and 

 broadens considerably to an obliquely truncate apex. At one corner of the apex are 

 two short stout spines terminating in two processes, the outer one rather stout and 

 blunt and microscopically ridged, the inner one slender and acutely pointed. At the 

 other corner of the apex is placed a long, strong, slightly curved spine with about 

 eleven spinules on the distal half of its margin. At the base of this long curved spine 

 is situated a smaller, more slender and more sharply curved spine and between this 

 latter spine and the two spines with the bifid apices, there is an obtusely pointed pro- 

 cess, microscopically ridged at its apex, which arises from some way inside the distal 

 margin of the fifth joint, on its lower face. The whole of the fifth joint resembles a 

 sub-chelate "hand" with the bifid spines delimitating the palm on one corner, 

 and the long curved spine as the " finger." 



Length of an adult female, 7 mm. ; of an adult male, 6 mm. 



This species is very closely allied to G. spinifer, Goes, but differs in the following 

 points : — 



(1) The absence of the dorsal spiniform process on the fifth segment of the pleon. 



(2) The larger number of spines on the lateral margins of the telson, fourteen as 

 against six to eight in G. spinifer. 



