502 Records of the Indian Museum. [\'ol. VIII, 



belong to the genus Spiraculum. In figures 2c and 36, within the 

 aperture may be seen the little orifice having a connection with 

 the branchial sac. In Spiraculum minimum this is very close to 

 the aperture, in Spiraculum putaoensis it is more remote. In the 

 first the inner and outer lips of the peristome are united and thick- 

 ened at the upper inner margin next the suture, while in the second 

 there is further development ; a clear separation of the lips has 

 taken place, the inner has a slight nick on the line of the suture, 

 shown by a sort of cicatrice up to the branchial orifice, and the 

 outer lip is expanded forward into a short scoop-like process corres- 

 ponding to the wing, as it has been called, of Pterocyclos. The 

 next species (fig. 4) might be placed in this genus and is a true link 

 with it. The tube is so far forward, it still forms a part of the 

 peristome, a complete isolated orifice has not yet been formed — it 

 is a slit ; the process of its further development would be the grow- 

 ing more forward of the whorl itself. In fig. 5, Spiraculum luyor- 

 ensis, we find this stage reached, and in fig. 5& the internal orifice 

 has been left behind, and externally a perfect tube is seen on the 

 suture (fig. 5^^) behind the aperture and completely separate from 

 it. While this evolution has been in progress, another change 

 has taken place- the scoop in fig. 4 has grown forward consider- 

 ably into the elongated gutter of fig. 5, with its edges growing 

 inwards and nearly touching, corresponding in life, in all proba- 

 bility, with a sharp fold of the mantle edge, which with further 

 growth might become more and more tube-like. 



Cyclophorus oakesi, n. sp. 

 (PI. xl, figs. I, la). 



Locality: Tsanspu Valley, Abor Hills, 2 specimens {Oakes), 



Shell globosely conoid, umbilicated, not widely. Sculpture, 

 a strong epidermis, fine lines of growth. Colour strong sienna 

 brown, mottled, broadish splashes of black. No peripheral band. 

 Spire somewhat depressed, apex broad and blunt. Suture im- 

 pressed. Whorls 4^, well rounded. Aperture circular, suboblique. 

 Peristome simple, not thickened, very slightly expanded, in the 

 best specimen it is not fully formed. Operculum horny multi- 

 spiral, smooth in front and concave. 



Size: major diam. 9*4 ; alt. axis 4*8 mm. 



Type No. 3083 Brit. Mus. 



The subgeneric position of this species is very doubtful ; the 

 animal has not been seen. 



Genus Alycaeus. 



Lieutenant, now Captain Oakes, R.E. was most fortunate 

 to secure some very interesting species of this genus. They all 

 proved to be new, one representing a new subgenus Raptomphalus. 



When these species were received, I was compiling a Mono- 

 graph of the Indian Alycaei for " Land and Freshwater Mollusca 



