MOLLUSCA OF INDIA, 127 



vel minus lata ejus loco posita^ interdumque nonnullis lineis riifis 

 ornata. 



" Habitat in insula Ceylon. 



" Obs. Distinguenda ab B. bistriali testae structura at sculptura, 

 anfractum et aperturee ratione, etc." 



Two specimens beautifully preserved in formalin were sent me 

 by Mr. CoUett, measuring 



(1) Diam. maj. 30'05, min. 26*5 mm. 



(2) „ 24-0 . „ 19-5 „ 



both with a narrow dark band on the periphery ; they both show 

 the form of the mantle-lobes almost as well as when the animals were 

 alive, and I selected the smaller of the two for dissection. The right 

 shell-lobe is narrow above, as in N. cliemd, decreasing gradually in 

 width down the side of the body- whorl to the posterior margin of 

 the shell ; the left shell-lobe is turned over the peristome for its 

 entire length. In this specimen, although the left dorsal lobe is 

 not divided, as it is in N. chenui, there is just the very faintest 

 indication of such division shown in a very slight cicatricial line, 

 and a slight indentation on the thin edge of the lobe. The other 

 specimen does not show this at all. The foot is not divided, and 

 under the lens it is longitudinally striated. 



The genitalia are of the same type as N. chenui. 



The odontophore is also similar in the form of the teeth (vide 

 Plate XCVI. figs. 8-S c) ; the formula diiiers, being 

 62 . 2 . 19 . 1 . 19 . 2 . 62 

 83 . 1 . 83 



The jaw is like the one figured on the same Plate, fig. 9 ; the 

 difference lies in the central teeth of N. cJienui being more numerous, 

 53 against 43 in N. ceylanica ; the two species are thus very closely 

 allied. It may here be pointed out that N. bistrialis of Madras, of 

 which the shell is certainly very much like that of ceylanica, so 

 much so that some conchologists have considered them inseparable, 

 differs only slightly in the number of teeth, eentrals=39. The 

 generative organs are on the same plan. I have never noticed in 

 the Madras specimens any sign of division of the left dorsal lobe. 

 The slight difference observable in the shells between those of the 

 Indian Peninsula and Ceylon is thus carried out in the animals. 



These South-Indian species are much wanted for examination, 

 as they may belong to Nilgiria : belangeri, bombayana, semirugata, 

 vitellina, sisparica, basilessa, bctsileus, madraspatana, &c. Ceylon : 

 jidiana, ganoma*, rosamunda, taprobanensis. 



Aeiophanta. 



{Continued from Vol. JI. p. 82.) 



As further material comes to hand, a better knowledge is afforded 



us of generic characters. Mr. W. T. Blanford has lately described 



(Proc. Malacol. Soc. London, vol. iii. pt. 5, p. 282, shell figured) a 



* While goiug to press I have received three specimens of this species. It 

 is remarkably close to N. chenui. They were also collected by Mr. Gollett, and 

 were kindly sent on to me by Mr. Blanford. 



