FRESHWATER GASTROPODA FROM MADAGASCAR. 885 



29. *Ampelita sepulchralis, FSruss. 



F&ussac, Hist. nat. Moll. i. p. 51. 



Anamalagotra and Tamatave-Marodasatia, 



30. *Ampelita xystera, Pfeif. (after Valenciennes, n. n.). 



Helix novacula, v. Martens, Nov. Goncli. 1879, vol. v. p. 181. 

 H. lanx, var., Feriissac, Hist. nat. Moll. i. p. .857, pi. 62. figs. 8, 9, 10 (1850). 

 H. xystera, Pfeiffer, Symbolfe, 1841, p. 41 (after Valenciennes, n. n.). 

 ?Ampelita Slum, E. A. Smith. P. Z. S. 1882. 



Tamatave-Marodasatia. 



Woods, liassic limestone, Ambongo. 



Woods, gneiss, Mangoro-Matitanavu, 300-600 m. alt. 



I did not think such a synonymy were possible ; but upon supplementing 

 Mr. Methuen's material with shells from the British Museum and others 

 kindly lent by Mr. J. H. Ponsonby, it became obvious that all the forms 

 indicated grade into each other by imperceptible degrees. 



Fam. Stenogyrid^. 



31. *Clavator clavator (Petit). 



Bulimus clavator, Petit, Revue Zool. 1844, p. 3. 

 Near R. Mangoky (S.E.). Woods, limestone soil. 



32. *Olavator eximius (S/mttleworth) . 



Spiraxts eximia, Shuttleworth, Mittheil. Bern, naturf. Ges. 1852, p. 208. 



Between Matitauu and Mangoro (E.) ; woods, 300-600 m. 



As Pilsbry (Man. Conchology, ser. ii. vol. xvii. p. 193) remarks, the 

 relation of Clavator to other genera cannot be intelligently discussed until 

 the sott parts are investigated. In addition, "the species resemble several 

 diverse groups in other regions. C. ohtusatus has a Stenogyroid contour, 

 C. Grandidieri is Placostyloid, and C. Balstoni, eximia, &c. resemble Than- 

 mastus^'' (Pilsbry, loc. cit.). Mr. T. Iredale, in addition, informs me that 

 C. eximia has often been taken for Placostyliis Bollonsi (New Z'aland) at 

 first sight. It is possible that this group is polyphyletic, and that anatomical 

 knowledge will serve to discriminate the various elements. 



Appendix. [June 3rd, 1914.] 



Since the foregoing account was drawn up some twelve months ago sundry 

 delays have hindered its publication. The author therefore avails himself of 

 the present opportunity to remedy in some small measure the deficiency of 



