1921.] Fauna of the Chilka Lake : Amphipoda. 541 



and Chèvre ux makes no mention of the thickened character of the second antenna 

 and of the posterior peraeopoda found in typical specimens of 0. platensis. 



[A very abundant sand-hopper all round the lake wherever the shore is sandy. 

 It remains concealed in burrows in the sand, especially under decaying weed, in the 

 heat of the day but is abroad in the evening and early morning. Many animals feed 

 upon it, including a pigmy shrew (Pachyura h&dgsoni), geckos (Hemidactylus frenatus 

 and H. brookei) and a dragonfly (Brachythemis contaminata) , which catches it on the 

 wing as jt hops in the evening. We have never found it except on the foreshore. 

 N.A.] 



Talorchestia martensii (M. Weber). 



(Text-fig. 8.) 



Orchestia martensii M. Weber, 1892, p. 564, fig. 13 — t6. 

 Talorchestia martensii Stebbiag, 1906, p. 553. 



Localities :— Barkul, Chilka Lake. ''Living in holes in mud under dead leaves 

 and weeds," Dr. N. Annandale, 21-VÜ-13. Several specimens, in associa- 

 tion with Orchestia platensis. 

 Off Barkul, 3-4 ft. One large male. 

 Satpara, edge of lake. One male, one female. 

 Barkuda Island. Several. 



Specific Diagnosis : — 



Male. Pleon segment 3 having postero-lateral corner with produced point. 

 Antenna 1, second joint of peduncle the longest, flagellum shorter than pedun- 

 cle, 5-jointed. Antenna 2, ultimate and penultimate joints of peduncle subequal 

 and long, especially in fully developed males ; flagellum nearly as long as peduncle, 

 with about 20 joints. Gnathopod 1 with carpus much longer thaö the propod, 

 produced distally into a narrow but well marked lobe ; propod very slightly widened 

 distally, distal lobe rounded, slightly shorter than the lobe on the carpus; palm 

 short, concave; finger long, reaching far beyond the rounded lobe. Gnathopod 2 

 with basal joint and ischium grooved anteriorly for reception of propod when 

 reflexed; the anterior margin of the basal joint with a regular row of about 10 

 distinct spinules in slight serrations; posterior margin with a smaller number of 

 similar spinules ; propod ovate, palm oblique, slightly convex, a little longer than 

 the straight hind margin and marked with v a double row of stout spinules, between 

 which the finger lies when closed ; a few small spinules on the hind margin ; ante- 

 rior margin convex and free from spinules; finger with inner margin concave near 

 the base, followed by a rounded enlargement, whole inner margin with minute 

 spinules. Basal joints of the 3rd-5th peraeopods well expanded, anterior margin 

 convex, fringed with spinules; posterior margin straight with rounded corners and 

 also fringed with spinules; none of the more distal joints specially enlarged. Telson 

 narrowing towards the extremity, divided by a shallow emargination at the end 

 into 2 small lobes, each bearing 3 spinules at the extremity, 3 or 4 other spinules 

 being placed laterally on the telson itself. 



