TRITONIDEA UNDULATA. 155 



NOTE XVII. 

 ON THREE EASTERN MOLLUSKS 



BY 



M. M. SCHEPMAN. 



1 ritonidea undulata, n. sp. 

 (Plate 9, fig. 1). 



Shell fusiformly ovate, yellowish, with brown spiral 

 ridges. Whorls about 6 , the apical ones , which are slightly 

 eroded , appear smooth , the rest rather convex , depressed 

 near the sutures, vertically ribbed with large swollen ribs 

 of which there are from 10 to 14 on the penultimate 

 whorl, and spirally ridged with 4 or 5 waved ridges on 

 the upper whorls, with finer intermediate ones. On the 

 last whorl , the ribs and waves become obsolete about the 

 periphery ; this whorl is encircled with a large number of 

 spiral ridges of which from 10 to 12 form conspicuous 

 brown lirae, with from 1 to 6 intermediate ones. Aper- 

 ture occupying more than half the length of the entire 

 shell, ovate, pale blue within, lip thickened exteriorly, 

 internally with about 10 ridges forming small denticula- 

 tions towards the lip. Columella callous , slightly excava- 

 ted above, towards the middle with a few small tuber- 

 cles on the left margin and a more conspicuous one near 

 the upper part of the aperture. Canal short, oblique. 



Length 26, diam. 16, length of apert, with canal 14 mill. 



Hab. Japan , collected by von Siebold (Leyden Museum). 



This species approaches in form T. fumosa Dillw. r= pro- 

 teus Reeve , in colour T. undosa Linn. , but differs from 

 both in form and sculpture. T. suhruhiginosa Smith should 

 ;>rotes from tlie Leyden. IMuseuxu, Vol. XIII. 



