1875.] Nieio Species of Zonitidae. 5 



Extremity of foot to posterior end of the mantle,... 1*9 inch. 



Mantle, 15 



Anterior end of mantle to head, 0'9 



Total, 4-3 



Eye tentacles, 0*42 



Helicakiou Shillongense, var., Plate II, Fig. 1. 

 Animal dark umber brown, body concolorous, the mantle a shade light- 

 er, nearly covering the shell in both varieties, the foot beneath is ash-colour- 

 ed ; when taken fresh there is a slight indentation at the anterior edge of 

 the mantle (vide fig.). Shell as in fig. 1 a. 



Extremity of foot to posterior edge of mantle, ... 1*70 inch. 



Mantle, 1-70 



Anterior end of mantle to head, 095 



Total, 4-35 

 Eye tentacles, 045 



Sab. — Shillong and North Khasi Hills. Both these forms are near 

 S. Theobaldi, but may be distinguished at once by the absence of the 

 white stripe on the edge of the left lobe of the mantle, and by the longer 

 form of the shell. The tentacles are longer than in JET. brunneum. 



Helicabion betjiweum, n. sp., Plate II, Eig. 2. 



Animal a rich brown, mottled on the mantle with dark sepia, dis- 

 tinctly marked with parallel streaks, that extend from a zigzag line run- 

 ning along the side of foot, the margin of which is edged below with a series 

 of short parallel markings ; foot beneath dark ochre. Large portion of shell 

 exposed, which is of same form as that of H, Shillong ense. 



Dimensions when fully extended : 



Extremity of foot to posterior end of mantle, 1*5 inch. 



Mantle, 1*6 



Anterior end of mantle to head, 0-47 



Total, 3-57 



Eye tentacles, 032 



Breadth of body, . ... 0-56 



Sab. — Shillong, Khasi Hills, in grassy localities. 

 Helicaeion Nagaense, n. sp., Plate II, Fig. 3. 

 Animal ochre colour, prettily mottled and dotted with a darker shade 

 of the same, the mantle covers nearly the whole shell ; a narrow white line 

 commencing near the posterior margin of the slit disclosing the shell, ex- 

 tends round towards the respiratory orifice on the right hand side, and in 



