G8 Contributions to Indian Malacology. [No. 1, 



No. 29, Teredo ? sp. 



All the dead trees in creeks in the Irawady delta are perforated 

 throughout by a species of Teredo (?) I either omitted to take speci- 

 mens, or else have lost them since, and I can now find none to "which to 

 refer. It is possible that this shell may be the Teredo tlioracites of 

 Dr. Grould,* described in Vol. VI, of the Proceedings Boston Society 

 of Natural History, and on which he subsequently, in Vol. VIII, pro- 

 posed to found the subgenus Calobates, characterized by the " pallettes" 

 (stylets) being " stilt shaped, bony." Dr. Gould's specimens were 

 from Tavoy, but he does not mention if they were fluviatile or 

 marine. 



Family CORBULID^. 



No. 30, Sphenia perversa, n. sp. PL III. fig. 4, 5, 6. 



Testa oblongo-ovata, parum intequivalvis, valvd dextrd majori 7 

 tenuiuscula, alba, concentrice irregulariter striata, antice rotundata, 

 postice acuminata, clemum transverse truncata, ad extremitatem epider- 

 mide coriaced, rugatd induta ; margo dorsalis subrecta, ventralis antice 

 convexa, postice vix concavd. Processus cardinalis valvce sinistra (non 

 dextrce) elongato-lamelliformis. 



Lat. 11, long. 6, alt. 4 mill. 



Shell oblong, slightly inequivalve, broadest at the umbo, somewhat 

 acuminate posteriorly, and very much more so in young specimens ; 

 thin, white, irregularly striated, the posterior end covered with a thick 

 coriaceous epidermis which is vertically furrowed. In the young 

 shell the epidermis covers all the shell except the beaks ; it is thin 

 except along the dorsal and posterior margins, where it is thick and 

 vertically sulcated. The dorsal margin is nearly straight, the ven- 

 tral rounded in front and slightly concave behind in old shells, straight 

 or nearly so in young specimens. There is a lamelliform process in 

 the hinge of the left valve, in front of the cartilage. 



This shell was met with in burrows in stone, apparently the holes 

 of Martesia which had perished, at least they did not appear to have 

 been formed by the present species. It was met with at a considerable 

 distance from the sea, in company with Martesia fluminalis. 



In every respect, except the position of the lamellar tooth in the hinge 

 of the left valve instead of the right, the shell appears to be a true 

 * Otia Conchologica pp. 222, 241. 



