252 Memoirs of the Indian Museum. [Vol. V, 



Cocnobita rugosus, Milne-Edwards. 



1915. Coenobita rugosus, Henderson, Rec. Ind. Mus., XI, p. 29. 



Two very young specimens were obtained in the outer channel between Manik- 

 patna and the mouth of the lake. They were found crawling on the sandy shore of 

 the outer bar in company with C. cavipes, and were living in shells of Natica. 



At the time when they were obtained the water in the outer channel was fresh ; 

 but alterations in salinity must be of very little consequence to species of Coenobita, 

 for they are typical land-hermits and live for the most part above water-level. 



The geographical range of the species, according to Alcock, is Tropical West 

 Africa: Red Sea littoral and Bast Africa , through the Indo-pacific to Vancouver, 

 Lower California and Coquimbo. 



Coenobita cavipes, Stimpson. 



1 9 15. Coenobita cavipes, Henderson, Rec. Ind. Mus., XI, p. 29. 



Small examples of this species were common at all seasons in the outer channel, 

 both when the water was fresh and when it was salt. When the water is at its 

 lowest, specimens may be found under the dry felted coating of algae which is exposed 

 on the shores of the backwaters and among the islands. On the clean sand near the 

 mouth of the lake the species is met with either walking in the open or sheltering in 

 the burrows of Ocypoda and under drift wood. 



A single large individual, with carapace 27 mm. in length, was obtained in 

 December inhabiting a shell of Ampullaria. This gastropod is common in fresh 

 water in the neighbourhood, but does not occur in the lake itself. The smaller speci- 

 mens were living in shells of Nassa, Potamides and Natica. 



Coenobita cavipes has a wide Indo-pacific distribution extending from E. Africa 

 to the Loo Choo Is. 



Tribe THALASSINIDEA. 



Family CALLIANASSIDAE. 



Subfamily CALLIANASSINAE. 



Genus CALLIANASSA, Leach. 



1903. Callianassa, Borradaile, Ann. Mag. Nat. Hist. (7), XII, p. 544. 



The single member of this genus found in the Chilka Lake is identified with a 

 form described by A. Milne-Edwards from a claw obtained in a sub-fossil condition 

 in Siam. The species is closely allied to one found on the west coast of Africa, 

 which appears triennially in the rivers in great numbers. 



Callianassa (Callichirus) maxima, A. Milne-Edwards. 



(Plate XIII, figs. 1-5.) 

 1870. Callianassa maxima, A. Milne-Edwards, Nouv. Arch. Mus. Paris, VI, p. 97. 

 The rostrum is sharply pointed, without lateral teeth, and is short, reaching 

 barely to one-third the length of the eyes. There is no tooth on the frontal margin 

 of the carapace between the eyes and the antennal peduncles (pi. xiii, fig. 1). 



