DUEGELLA. 215 



extremity of the foot, also on the neck, tentacles moderately 

 long. 



JMantle-lobes moderately developed. Spermatbeca thick, short, 

 and wide at the base, with a swollen wide terminal portion. 

 Dart-sac large, cylindrical, but twisted in form. The vas deferens 

 joins the male organ close to the retractor muscle ; without 

 kale-sac. 



The teeth in the radiila exceed 170 . 1 . 170 : the rliachidian tooth 

 is very minute; the laterals very numerous and closely set together, 

 their upper edge serrated with 5 or G points each, and they 

 diminish gradually in size outwards. There are upwards of a 

 hundred rows of teeth in the odontophore. The jaw is very thin 

 and membranaceous, nearly straight in front. 



[319. Durgella rogersi, Godwin-Austen, Mol. Lid. ii, 1907, p. 205, 

 pi. 11"), figs. 4, 4 a, pi. 116, figs. 7, 7 a. 



Shell globose, very thin, membranaceous : it was impossible to 

 remove the animal preserved in .spirit without tearing it. AVhorls 

 Sg ; colour pale straw, apex flatly rounded. 



Hah. Paphunta Valley, South Andamans {G. Borjers). 



Animal about 20 mm., contracted in spirit. Foot long behind, 

 pointed, keeled, narrow ; sole divided ; peripodial grooves with 

 parallel streaking running fi'om them to the margin of the foot. 

 A fairly large rounded right shell-lobe rising on the side of the right 

 dorsal lobe ; the left shell-lobe smaller than the right, rounded on 

 the margin ; both shell-lobes somewhat thickened, pale-coloured, 

 unmarked, and smooth. 



The genitalia were not, unfortunately, got out in a state for 

 description. The penis is simple, like that of D. levicida ; no 

 amatorial organ seen. 



Jaw veiy thin, almost straight in front, only a slight convexity 

 in the middle. 



Radula consists of an enormous number of teeth ; there are at 

 least 500 in the row, and 70 rows can be counted. It was got out 

 in a nearly perfect state, but the filmy edges got folded under it ; 

 and it is most difficult when this occurs to spread them out again, 

 rendering counting impossible. The teeth are more numerous in 

 this radula and more minute than in any I have seen hitherto ; 

 they are in form of similar type to those of Dair/ella levicida and 

 mairanr/ensis, of Tenasserim and the Khasi Hills respectively, but 

 still closer to the outermost teeth of Durgella ? sumbaensis, G.-A, 

 (vide Mol. Ind. vol. ii, pi. 79, fig. 8 h), which may possibly belong 

 to Lainprocijstis, and points to this last genus having a position 

 rather with the subfamily Durgellime than any other.] 



320. Durgella concinna, sp. n. 



Nanina levicula, JJlf. J. A. S. B. 1865, 2, p. 87, pt. ; Kevill, Hand-l. 

 i, 1878, p. 26, pt. : nee Bs. 



Shell subperforate, depressedly globose, fairly solid, smooth, with 



