62 NANTNA. 



N. VULCANI, Godwin-Austen. PL 26, fig. 60. 



Longitudinally moderately closely ribbed, radiately ribbed 

 below; color (bleached) probably horny; whorls 6, with shallow 

 suture, the last with angulated periphery. Diam. 3, alt. 2*3 mill. 



Upper Burmah. 



aa. Spire = or exceeding the major diameter. 



N. SIGURENSIS, Godwin-Austen. PI. 26, fig. 61. 



Subperforate, rather finely longitudinally ribbed, well developed 

 on the base, no spiral sculpture; umber-brown; whorls 7, con- 

 vex, the last whorl with obtuse keel. Diam. 3'25, alt. axis 3 mill. 



Nilghirri Hills, India; Madagascar. 



N. CHERRAENSIS, Godwin-Austen. PI. 26, figs. 62, 60. 



Scarcely perforate, longitudinally very finely regularly costu- 

 late, very finely, regularly, spirally sculptured on the base; color 

 dull brown ; whorls 6, a distinct sulcation on the keel of the last 

 whorl. Diam. 2'5-3, alt. axis 2-3-3 mill. 



Khasi Hill* ; Lower Bengal. 



The latter country furnishes a slight varietal form (fig. 63). 



aaa. With strong, distant costulation. 



N. COSTULATA, Godwin-Austen. PI. 26, fig. 64. 



With distant, very distinct ribs terminating at the peripheral 

 keel, irregularly spirally striate below; very pale olivaceous 

 brown ; whorls 6, suture margined by the peripheral rib. 



Diam. 3'3, alt. axis 2'8 mill. 



Do fi.a Hills, Assam. 

 Not fully adult. 



N. SUBCOSTULATA, Godwin-Austen. PL 26, fig. 65. 



Perforation covered, with well-defined longitudinal costulse 

 above, and fine radiating stride on the base ; pale sienna-brown ; 

 whorls 6, the last rather strongly keeled. 



Diam. 2'8, alt. axis 2 mill. 



A 7 . Khasi Hills, India. 



b. Spire high, sides convex, subangulate on the periphery. 

 N. MUNIPURENSIS, Godwin-Austen. PL 27, figs. 66, 67. 



Very finely longitudinally costulate, the sculpture continuing 



