XXI. THE GENUS TEMNOTAIA (VIVI- 

 PARIDAE). 



By N. Annandai,E, D.Sc, F.A.S.B., Director, Zoological Survey of 



India (on leave). 



The genus Temnotaia was proposed by myself in 19 ro as a 

 subgenus of Taia, mihi; but in the following year I gave reasons 

 for considering it distinct. A reference to the collection in the 

 British Museum enables me to throw further light on the genus. 

 I have to thank Mr. G. C. Robson for giving me full facilities for 

 examining the specimens and Mr. J. R. le B. Tomlin for supply- 

 ing me with the reference to Mabille's description of the allied 

 Indo-Chinese genus Chlorostracia and lending me a copy of the 

 scarce work in which it is contained. The Burmese genus may 

 now be more fully described and its relations to Chlorostracia 

 discussed. 



Temnotaia, Annandale. 



igig. Temnotaia, Annandale, Rec. Geol. Sur. hid. I., p. 231. 

 1920. Temnotaia, id., Hec. Ind. Miis. XIX, p. 115. 



The shell is typically Vivipariform in outline, but thick and 

 porcellaneous. It is ovoid, acuminate and imperforate, with 5 J 

 to 7I whorls, which increase in size gradually and never have 

 the suture deeply impressed. In all the species yet known the 

 umbilicus is imperforate. The body-whorl is never greatly swollen 

 and the aperture is of moderate size, ovoid and slightly oblique. 

 The external surface is smooth and highly polished in fresh shells, 

 with a very thin, closely adherent periostracum. The sculpture 

 consists of incised lines or very fine linear ridges or else is micros- 

 copic. Interrupted broad ridges, nodules, scales and spines are 

 entirely absent. The columellar callus is short and broad, convex 

 and highly polished. Dark spiral bands are present or absent. 



The operculum resembles that of Vivipara and is moderately 

 thick. Nothing is known of the radula or soft parts 



Tcnuiotaia differs from Chlorostracia ' mainly in its much more 

 normal outline and in the structure of the operculum. The shell 

 of the latter genus, of which a considerable number of species 

 occur in Siam and French Indo-China, has a curiously 'Natica-)\ke 

 facies owing to its short spire, relatively large penultimate whorl, 

 deep suture, perforate umbilicus, immense body- whorl and large 

 aperture. Its operculum is characterized by the very large inter- 

 nal scar, which bears a curious crateriform process. 



J Mabille, Bull. Soc. Mai. France VI, p. 3og(l889\ The type-species is 



C. bocourtei, Mabille, the shell and operculum of which are figured in the same 

 paper. 



