BACILLUM. 343 



Bnigaiere's description is not very clear and I have therefore 

 added the diagnosis given by Pilsbry in his admirable account of 

 the s])ecies. The bibliography covers more than two octavo pages, 

 but I liave limited myself to the principal references and those 

 having any bearing on its occurrence in the Indian region. 



The Beddome collection in the British Museum contains, 

 amongst specimens from numerous Avidely separated localities, 

 three shells from Bombay, composed of ten whorls and measuring 

 19 mm, in length. 



Genus BACILLUM:, Theobald. 



Bacillum, Theobald in ITanley & Theobald, Conch. Ind. 1870, p. 17 

 (as subgenus oH Achat ina for A. ohtusa, Blanford, and A. casiaca, 

 BcHSon) ; Pilsbry, Man. Conch, ser. 2, xviii, 1906, p. 1. 



Type, Acliatina casiaca., Benson. 



Range. Eastern India. 



" Shell rather large, solid, imperforate, turrited, many-wborled, 

 a little conti'aeted near the obtuse, rounded summit, the em- 

 bryonic shell cyliudric ; sculpture of vertical rib-strise beginning 

 somewhere upon the first whorl : the post-embryonic whorls being 

 obliquely, regularly rib-striate. Aperture oblique, Achatinoid, 

 the columella concave, truncate at the base, outer lip simple. 

 Internal axis slender, strongly sigmoid within each whorl. Soft 

 anatomy unknown." (Pihbnj.) 



" This group would hardly be thought distinct from Homorus, 

 were it not well separated geographically from that African genus, 

 at least in the recent fauna. Almost the sole distinguishing feature 

 is the stronger sculpture of Bacillum. Both groups ai'e merely 

 large and solid forms of the Suballiia type, so far as the sbells are 

 concerned." (Pilsbrij.) 



302. Bacillum daflaensis, Godwin- Austen. 



Glessula dajlaensis, Godwin-Austen, J. A. S. B. xlv, LS76, p. ."ilG, 

 pi. 8, fig. 10. 



Original description : — " Shell elongately turreted, thick, ob- 

 liquely striate, covered with a thick olive-green epidermis with a 

 few dark streaks. Spire turreted, slightly convex in outline, apex 

 blunt ; whorls 11, rather flat, specimens with the apex preserved 

 shewing erosion of the surface. Suture well marked. Aperture 

 oblique, suboval, pale grey. Peristome acute, columellar margin 

 slightly curved and but little thickened. 



''Alt. 1-9 [=48 mm.], major diam. 0-41 [ = 10-o mm.], alt. 

 ap. 0*42 [ = 11 mm.]." {Godwin- Austen.) 



Hab. India : Shengorh Peak, Dafla Hills {Godwin- Austen). 



"This shell woidd appear to have a close connection with 

 G. erosa, II. Blf., from Darjiling, but its much longer form. 



