Records of the Indian Museum. [Vol. VIIT, 



Largest sp. . , major diameter 13-0, alt. axis 5-5 mm. 

 Ordinary size .. ,, lo'o ,, 4-8 ,, 



Animal. In the spirit specimens the very much darker colour 

 of the visceral sac, much speckled and mottled throughout at once 

 showed this to be a different species to the first I dissected from 

 the Naga Hills. The mantle edge has a broad band of black. The 

 visceral sac as far back as the region of the heart is blue black 

 with a narrow pale ochre band on the line of the rectum, which on 

 closer inspection is made up of closely set double V-shaped mark- 

 ings. 



In the generative organs (text-fig. 4, A, B, C, D), the penis is 

 very small in comparison to the length of the free oviduct and 

 albumen gland. It is bent on itself where the short retractor muscle 

 is given off, the epiphallus is short up to where a short thick ovoid 

 sac, which represents the flagellum, occurs, the vas deferens joins 

 this at its base, takes a few twists and continues to the oviduct. 

 The spermatheca is a long thin duct with a fairly large globose 

 termination (fig. 4, D), which is generally broken off in the process 

 of dissection. The salivary glands were well seen with the buccal 

 mass, two separate masses on long fine ducts (fig. 4, E). 



The jaw (text-fig. 5, D) is composed of some 24 plates closely 

 set together. Radula formula 15.1. 15. 



The r6th tooth is bicuspid and the next four are similar. 



Landouria hcngdanensis, n. sp. 



(Text-figs. 2 E and text-fig. 5 A, B, C). 



Locality. — Hengdan Peak, Burrail Range, on the North Cachar 

 and Munipur Frontier {Godwin- Austen). 



Shell globosely conic, veiy flat on the base, openly umbilicated, 

 sculpture smooth, fine lines of growth, indistinct spiral striation 

 near the umbilicus; colour pale brown. Spire rather high, sides 

 slightly convex, suture shallow. Whorls 5, the last rounded, sides 

 slightly convex, aperture semilunate, columellar margin oblique. 



Size: major diameter ico, alt. axis 4'5 mm. 



This shell is more openly umbilicated than H. huttoni. 



Animal. The branchial sac is very long, pale ochre, a dark 

 line borders the mantle edge, and on the line of the rectum there 

 are 8 or 9 conspicuous spots of black. The generative organs were 

 not in a state to see very much^ or to figure. 



The jaw is highly arched with about 24 close set plates. The 

 central teeth are simple and straight sided, at the 6th tooth a 

 small cusp begins to show and continues to the 17th, becoming 

 larger, at the i8th the mesocone is bifid and this is the shape with 

 an outer single cusp up to the margin, where three or four of 

 the outermost laterals have double cusps on the outer side of the 

 bifid mesocone. 



Radula formula 14.12. 1. 12. 14 or 26.1.26. 



