Mr. W. H. Benson on Freshwater Shells from India. 257 



third cells oblong, the fourth extending to the apex of the wing. 

 Legs simple, elongate ; the tibiae armed with two short spines at 

 their apex. 



Cladomacra macropus. 



C. nigra ; capite, thorace, abdominis basi, coxis femoribusque rufo- 

 testaceis ; antennis elongatis, pectinatis ; alis fumatis, venis fuscis. 



Male. Length 3 lines. Black; the head, thorax, and ex- 

 treme base of the abdomen rufo-testaceous ; the head with a 

 deep depression on each side ; the antennae emanating from a 

 short basal footstalk, one-third longer than the body, and pecti- 

 nate ; the teeth or branches elongate and pilose. The wings of 

 a smoky brown, iridescent, with the nervures dark brown. The 

 legs longer than the body ; the coxae, trochanters, anterior and 

 intermediate femora, the base of the posterior pair, and the 

 anterior and intermediate tibiae inside, rufo-testaceous ; the 

 posterior tibiae and tarsi with short black pubescence. 



This beautiful insect, for which I am obliged to establish a 

 new genus, has been received from Mr. Wallace, who captured 

 it in Celebes ; the neuration of the wings, and general habit of 

 the species, appear to indicate clearly its affinity to the genera 

 Cladius, Trichiocampus, and Nematus, from all of which it is 

 separated by having four submarginal cells, and antennae com- 

 posed of sixteen joints. The normal number in the Tenthredinidae 

 is nine joints ; but there are several genera which depart from 

 that number : thus, in Sir ex there are twenty-five, in Xiphydria 

 thirteen, whilst in Lyda the number varies, in the different 

 species, from twenty-one to thirty-four. 



XXXIII. — Descriptions of Freshwater Shells collected in Southern 

 India by Lieut. Charles Annesley Benson, 45th M.N.I. By 

 W. H. Benson, Esq. 



The following shells were discovered at Quilon, on the Malabar 

 coast, in the territory of Travancore, a portion of country which 

 appears hitherto to have escaped the researches of conchologists. 

 Among other species, the little-known MelaniaRiquetii, De Grate- 

 loup (figured and described by that author in the ' Acts } of the 

 Nat. Hist. Society of Bordeaux), from Bombay, was found to 

 accord perfectly with the published type, which appears to have 

 been subsequently described by Lea under the designation of 

 M. Tornatella. The figure in the 'Iconica' (173 6) delineates 

 the sculpture of M. Riquetii, while that given at 173 a agrees 

 better with Souleyet's M. sculpta, a species which was found by 

 the late Dr. Bacon at Singapore. I have seen one of the nu- 

 merous varieties of Melania lirata t B. (J. A. .S. 1836, sub- 



