85 



Turbonilla Beddomei, Petterd, sp. 



1884. Chemnitzia Beddomei, Petterd, Jour. Conch., p. 136. 



1892. Turbonilla crenulifera, Tate, Trans. Roy. Soc, S. Aust., 

 XV., p 126, t. 1, f. 2. 



The specimens, attributed to Petterd's species, given me by- 

 Mr. May, leave no doubt of the identity of my shell therewith, 

 though the diagnosis of the Tasmanian shell does not refer to the 

 tendency of decresence of the costae on the anterior aspect of the 

 whorls, and to crenulation at the posterior suture. 



So far as known to me. the species is restricted to South 

 Australia and Tasmania. 



Turbonilla varieifera, Tate, 1898. Pi. iv., fig. 7. 



Shell elongate turreted, about four times as long as broad 

 usually of a chestnut-brown colour, with the varices mottled with 

 white, but various shades passing to white occur. Spire-whorls 

 twelve in a length of fifteen millimetres, tipped by a heterostrophe 

 protoconch ; flatly convex, but separated by a well-defined 

 suture ; ornamented by close-set, slightly oblique, rounded, axial 

 ribs, separated by much narrower interspaces, here and there two 

 ■or more costse are confluent to form a broad varix ; the whole 

 surface is crossed by incised spiral lines increasing to about fifteen 

 on the penultimate whorl of a large specimen. Last whorl with 

 axial costse, about twenty, evanescent at the regularly rounded 

 periphery ; base spirally linear-sulcate ; aperture oblong, columella 

 with an obscure spiral plication. 



Long,, 15 mm. ; lat., 4-00 mm. A micromorph of twelve spire- 

 whorls measures 10 mm. by 2-5 (vix) mm. 



This species has been represented in my cabinet for many years 

 by incomplete beach-examples, which indicate a very large shell 

 ior the genus and the possession of varices. Its recent discovery 

 in some numbers by Dr. Verco, through dredgings in the deeper 

 parts of St. Vincent and Spencer Gulfs, has, now, made it possible 

 to adequately diagnose the shell. 



The feature of the variced spire, though exceptional, is how- 

 ever, presented by the recent species, T. striatula, Linne (the 

 type of Montserrato's Section Pyrgostylus) and the Miocene 

 species, T. intermedia, Grateloup ; both of which I have under 

 observation. 



The Australian species, making the third enumeration under 

 Pyrgostylus, differs from T. striatula, chiefly by its straighter 

 costae and narrower interspaces ; and is distinguishable from T. 

 intermedia by slenderness, less oblique ribs with narrower 

 interspaces. 



