414 LAND AND FBESHWATER 



interest, as it extends the range of this species for 270 miles 

 north up the valley of the Irrawaddy. 



Alyc^us woodthokpi, n. sp. (Plate CLV. fig. 14.) 



LocaUf.!/. Fort Stedraan, Burma. No. 3064 G.-A. Coll., B.M. 

 {Colonel Ji. Woodthorpe, R.E.). 



Shell openly umbilicated, globosely conoid ; sculpture : oblique, 

 sinuate costulation on upper whorls rather strong and distant as 

 it approaches the end of the sutural tube, it then becomes very 

 fine and very close up to the constriction ; colour pale sienna- 

 brown ; spire moderately high, apex small ; suture well im- 

 pressed ; whorls 4, the constriction near the base of the sutural 

 tube, thus enlarging into a narrow costulated ridge which is close 

 behind the peristome ; aperture oval, obtusely angulate above ; 

 peristome simple, double, thick, columellar margin curving 

 vertically. 



Size : maj. diam. 4-3 ; alt. axis 2-0 mm. 



The most distinguishing character of this shell is the extremely 

 fine close regular costulation next the sutural tube, which, in 

 most species of the genus, is strong and well defined ; this cha- 

 racter is met with again in species of the Abor Hills, such as 

 A. ahorensis, (fee. This in conjunction with the fact that so large 

 a proportion of species in other genera inhabiting the Abor countrv 

 are not found in Western Assam, is an indication of topographical 

 connection between the Shan area and the Tsanspu drainage- 

 system far back in geological time, closer, more direct, and 

 unrestricted than now exists. There are grounds for thinking that 

 the high snowy range at the head of the Irravady, together with 

 the well defined orographical feature the Assam Kango to the west, 

 may be a comparatively recent elevation compared to the main mass 

 of the Eastern Himalaya. 



Alto^us (Dioryx) itrntjla, Bs., var. 



Godwin-Austen, P. Z. S. 1888, p. 245, in paper " On Some Land- 

 Mollusks from Burma." 



Locality. Pingoung, Shan Hills (2500 ft.). 



" The only difference between this and the Assamese forms is 

 the greater length of the sutural tube in the Burmese shell." 



Mr. John Ponsonb}', in whose collection it is, has most kindly 

 let me have it to figure. I describe it below. 



A single, not very well-]>reserved, Dioryx from Munipur 

 (Pi. CLIII. fig. 10) is somewhat similar, but is more globose and 

 not so high in the spire. 



Altc^us (Dioeyx) pingoungensis, n. sp. (Plate CLIII. 

 figs. 13, 13 a.) 



Locality. Pingoung, Shan Hills {Captain Spratt, ex coll. J. Pon- 

 sonhy). 



Shell solid, imperforate ; sculpture very smooth, surface with 

 indistinct transverse strialion, next the sutural tube there is fine 



