I9 I 5-] Fauna of the Chilka Lake : Mvsidacea. 



159 



II. Endopod of the third pair of pleopods in the male, normal in form and 

 armature and multi-articulate. 



G. spinifer, G. sanctus, G. muticus, G. simulans, G. kojirnaensis (as far as 

 can be gathered from Nakazawa's meagre description). 



In this group the second pair of pleopods of the male has both the 

 exopod and endopod of normal form and armature and multi-articulate. 



Group I represents the old genus Haplostylus instituted by Kossmann for G. nor- 

 mani and later cancelled by Hansen (19 10) and merged in the genus Gastrosaccus. 

 Group II represents the old genus Gastrosaccus. G. vulgaris would seem to provide 

 the connecting link, since, according to Nakazawa's figures, the endopod of the third 

 pair of pleopods of the male is much reduced and only two-jointed, while the second 

 pair of pleopods of the male have both the endopod and exopod normal in form and 

 armature and multi-articulate. 



From the point of view, therefore, of the pleopods of the male, G. muticus and 

 G. simulans agree with G. spinifer and G. sanctus and are readily distinguished from 

 all the Indo-pacific species except possibly G. kojirnaensis, the description of which 

 is somewhat meagre. 



The specimens of G. simulans, obtained at Puri, were found at night at the 

 water's edge on a sandy beach facing the open sea. Their presence was detected in 

 the first instance owing to their brilliant luminosity, which was of a general nature. 



Sub-family MYSINAE. 



Genus MACROPSIS, G. O. Sars. 



Macropsis oriental is, Tattersall. 



M. orientalis, Tattersall, 1908, 1914. 



Further records : — Chittagong, pond at N.B. end of the town near the river, 

 January, 1913, coll. N. Annandale and S. W. Kemp. Abundant. 



Chilka Lake, abundant everywhere. 



Madras Harbour, 4-6 feet, October 1913, coll. N. Annandale. One. 



Cochin backwater, near Ernakulam, September 1914, coll. F. H. Gravely. 

 Fifty-eight. 



The last two records indicate an extension of the known distribution of this 

 species in the littoral of India, and it has now been found at a number of localities 

 situated at the head of the Bay of Bengal and on both sides of the Indian peninsula. 

 At Chittagong in the Gangetic Delta, and apparently at all suitable localities as far 

 south as Vizagapatam on the east coast, it is enormously abundant. It ascends 

 some at any rate of the larger rivers on this coast for a great distance, at least 40 

 miles above tidal influence ; but has not as yet been found in any isolated body of 

 water. In many places it occurs in water that is permanently fresh ; but it also 

 occurs in sea- water. 



In the Chilka Lake it is found everywhere, but most abundantly in the main area, 



