140 
Contributions to Indian Malacology. [No. 2, 
just referred to, although they have corresponding internal hollows, 
are scarcely so prominent as those forming the sculpture of the upper 
portion of the shell. They are nearer to the mouth than to the rise 
of the sutural tube, and lest upon a tumidity which is scarcely suffi¬ 
ciently pronounced to enable the species to be assigned to the section 
Charax of Benson, although it exactly represents the well marked 
ridge in the undermentioned species A. polygonoma. The sutural 
tube is, in one specimen, somewhat short of the typical length. 
Of A. succineus, I only obtained 4 specimens. They occurred at 
Moditoung together with A. graphicus, &c. All were dead, but in 
fresh condition. 
6. Alycasus polygonoma, n. s. 
Testa aperte et perspective umbilicata, turbinata, radiato-striata, 
rubello-succinea. Spira conica, apice obtusula, sutura profunda. 
Anfr. 4 rotundati, ultimus ad latus valde inflatus, ibidem confertis- 
sime et acute costulatus ; spatium constrictum longitudinis medio- 
cris, costulato-striatum, medio in postam prominentem, intus cavo-sul- 
catam, 2 vel 3 costulis signatam, tumescens. Tubulum suturale 
mediocre, 4 peripherise subsequans. Apertura obliqua, polygonali- 
circularis, basi valde antice sinuata; peristoma duplex; interno vix 
porrecto, margine dextro ter subangulato, basi subcanaliculato ; ex- 
terno incrassato-expansulo, processu brevi, acuto, basali munito. 
mm. 
inch 
Diam. maj. 
5 
or 0.2 
„ min. 
41 
0.17 
Alt. 
31 
0.14 
Ap. diam. 
H 
0.07 
Hab. in montibus Arakanensibus. 
This species is allied to the last described but is distinguished by its 
higher spire, less marked sculpture, by the strong ridge on the con¬ 
striction, and by the more polygonal aperture. The incision of the 
base, however, is slighter, and, in this species, accompanied by a slight 
corresponding projection beneath, which represents, on a small scale, 
the large ear-like basal process in A. prosectus Bens from the Kliasi 
Hills. The inner peristome of that species also has a slight basal 
indentation within the aperture. 
I am indebted for a few perfect specimens of this species to Captain 
Ingram, who found them upon the Western side of the Arakan range. 
