AMPHIDROMUS, S.-G. BEDDOMEA. 7 



A. ALBIZONATUS (Reeve). PI. 1, fig. 14, 15, 16. 



Shell somewhat pyramidally conical, rather depressed at the base, 

 scarcely umbilicated ; whorls seven in number, flatly convex, ob- 

 liquely finely striated ; sutures peculiarly linearly engraved ; last 

 whorl angled at the base ; columella broadly reflected ; bluish-white 

 within and without, having a narrow opaque white zone at the angle 

 of the last whorl (Reeve). Length 34, diam. 21^ mill, (from fig.). 



Ceylon (Taylor coll.). 



BuUmus albizonatus REEVE, Conch. Icon. pi. 81, f. 604 (Dec., 

 1849). 



" A pale, blue-white shell, remarkably characterized by a narrow 

 opaque-white zone round the middle of the whorls, exactly in the 

 place of the suture, concealed in all but the last whorl by the super- 

 position of one whorl upon the other." (Reeve.) 



Mr. E. R. Sykes, who kindly examined the type now in the 

 British Museum for me, states that a trace of minute pitting is 

 visible. 



Numerous specimens before me (pi. 1, figs. 14, 15) are smaller 

 than Reeve's type, measuring from length 29, diam. 18, to length 

 23, diam. 14 mill. The thin cuticle is more or less yellow tinted be- 

 neath, and the periphery either marked by a white line or not. The 

 angle is frequently almost completely obsolete on the face of the whorl, 

 even when strong on the back. The spire is punctulate or densely 

 subgranulose, at least above, but not on the lust whorl. They come 

 from Matella and " western province " of Ceylon, collected by 

 Layard. Fig. 14 shows the peripheral keel by far too strong; it is 

 almost imperceptible in the middle of the front of the shell. 



Kobelt (Conch. Cab. p. 680) states that he gives the figure from 

 the Conch. Icon, on his plate 103, f. 4, but he evidently did not do 

 so. His figure is a smaller variety probably referable to simoni. 



Var. SIMONI (Jousseaume). PI. 1, figs. 17, 18. 



Shell dextral, compressed-umbilicate, thin but moderately solid. 

 White under a thin pale buff, somewhat caducious cuticle; glossy, 

 faintly striate, very densely microscopically punctulate throughout. 

 Spire straightly conic, the apex obtuse. Whorls 5^ to 6, the first 

 two convex, the rest but slightly so; last whorl acutely carinated at 

 the periphery. Aperture very oblique, ovate ; peristome white, ex- 

 panded and reflexed, the columellar margin dilated above. 



