90 



Descriptions of New Genera and Species 



of Australian Mollusca (chiefly 



Tasmanian).* 



By Professor Ralph Tate and W. L. May. 



[Read October 2, 1900.] 



Lampusia nodocostata, spec. nov. 



Shell fusiform, rather slender, light-brown. Whorls (excl. 

 proto-conch) four and a-half, convex, but obtusely angulated in 

 the middle. Embryonic whorls incomplete, one and a-half 

 preserved, smooth, rounded, relatively large (2-75 mm. diam.), 

 suggestive of a styliform proto-conch similar to that of L. exarata, 

 but on a larger scale. 



Costse subacute, with about three nodulations on the anterior 

 half ; six intervariceal costse. Varices similar to the costse, 

 except that they are stouter ; seven in all. 



The spiral ornament consists of crowded threads, which are 

 obscurely granulated ; 24 on the penultimate whorl, of which 

 three on the anterior half of the whorl are broader, and originate 

 the nodulations on the costse. 



Last whorl about two-thirds the total length of the shell. The 

 costse are extended to the base, and the nodulation is continued 

 below the periphery, corresponding with the intercrossing of six 

 broader spiral threads, which are regularly disposed ; the inter- 

 stitial spaces between the broader threads are occupied by about 

 eight smaller spiral threads. 



Aperture quadrately oval ; beak short, considerably upturned. 

 The columella is smooth, and the outer lip is not dentate (the 

 shell is probably not full grown). 



Length, 31; breadth, 16; length of aperture and canal, 17mm. 



East Coast, Tasmania ; two examples ( W. L. May). 



This species appears from the description and figures of Triton 

 tenuiliratus, Lischke, Japan Meer-Conch., to be closely related 

 thereto ; but differs by details of ornament. T. granulatus y 

 Dunker, is the only Australian species of the genus unknown to 



* It is anticipated that figures of the new species and other unfigured 

 Tasmanian species will be published early next year by the Linnean 

 Society of New South Wales, to accompany a paper entitled " Revised 

 Census of the Marine Mollusca of Tasmania," as time does not permit of 

 their preparation to accompany this issue. 



