PLECT0PTLI8. 



113 



101. Plectopylis brahma, Godwin-Austen. 



Helix {Plectopylis) brahma, Godwin-Austen, J. A. S. B. xlviii, 1879, 



p. 3, pi. 1, tig. 3 (shell and armature). 

 Helix {Atopa {Plectojrylis)) brahma, Tryon, Man. Conch, ser. 2, iii, 



1887, p. 164, pi. 36, figs. 35-37. 

 Plectopylis brahma, Pilsbry, Man. Conch, ser. 2, ix, 1894, p. 145 ; 



Gude, Science Gossip, n. s. iv, 1897, p. 170, fig. 63 (shell and 



armature). 

 Plectopylis (Chersaecia) brahma, Gude, op. cit. vi, 1899, p. 148. 



Original description: — "Shell sinistral, rather closely umbili- 

 cated, discoidal, pale ochry-brown, finely and regularly striate. 

 Apex flat, yet slightly convex. Whorls 7, last angular above 

 and rounded below, slightly compressed behind the aperture and 

 hardly descending. Aperture luuate, oblique. Peristome slightly 

 reflected and thickened, white, continued as a callus on the body- 

 whorl. 



" Internal structure complicated ; the parietal vertical lamina is 

 strong and gives off a short horizontal lamella at the lower end ; 

 above this are two other and parallel /r^e lamellae (in three cases 

 out of twelve I examined, the upper lamella was united to the 

 vertical barrier, but this does not affect the order of position and 



Fig. 54. — Plectopylis brahma. 



arrangement of all those processes in this species), both short, the 

 lower being the best developed ; the upper is occasionally united 

 to the upper end of the vertical barrier. There is a very thin 

 thread-like lower free lamella extending to the peristome and 

 uniting with the parietal callus. The palatal plicoi are arranged 

 in two rows, those of the anterior row are few and large, four in 

 number, the two upper long, narrow, and adjacent, the 3rd is 

 a flattened dome-like mass, the 4th is long and curving inwards. 

 Behind this at a short distance is the second row, consistino- 

 of fourteen very minute, closely arranged, thin, longer or shorter 

 tooth-like processes, those on the upper side being shghtly the 

 largest." ( Godivin- Austen.) 



Major diam. 9, minor 8"5 mm. ; alt. 5 mm. 

 Hab. Assam : Brahmakhund (Ogle). 



Lt.-Col. Godwin-Austen states that in external form the present 

 species resembles P. shiroiensis, from which it may be distin- 

 guished by the coarser periostracum and more regular striation, 

 while the last whorl is not constricted near the aperture. The 

 parietal armature consists of a strong vertical plate having a short 



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