296 MB. E. A. SMITH ON THE 



a little above the base, and beneath it is convex ; and on the left 

 the lateral outline is less oblique than Sowerby represents it. The 

 aperture is equally curved at the base and above, and the subbasal 

 keel scarcely affects the curve of the right margin. 



106. PLA]!fOKBis sPinonBis, Miiller. 



Sah. Grreat Britain and Europe. North Australia (Mus. 

 Cuming). 



There are two tablets containing several specimens of this spe- 

 cies in the Curaingian collection labelled North Australia; and it 

 is for this reason that I include it in the Australian list. If there 

 had been but a single set of them, I should have been inclined to 

 think that possibly the label had been misplaced ; but since there 

 are two series, it becomes more probable that they are indeed 

 Australian examples. 



Genus Segmentina. 



107. Segmentina atjstkaliensis, n. sp. (Plate YII. figs. 

 7-10.) 



Shell dextral, glossy, chestnut, rather acutely keeled a little 

 below the middle of the last whorl, obliquely convex above the 

 keel, and ratlier flattened at the base. Spire sunken in the 

 middle. Whorls 4, convex, separated by a deep suture. Umbi- 

 licus deepish, occupying about one third of the diameter of the 

 base. Aperture liorizontal, much encroached upon by the whorl, 

 flat at the base, rather acute on the right. 



Greatest diameter 5 millim., smallest diameter 4, height 1^. 



Mab. Penritl), N. S.Wales {M'GilUvo^ay, Voyage of the'Battle. 

 snake'). 



The internal lamellae are somewhat difficult of observation 

 through the shell. Those nearest the aperture are situated at 

 about one third of the extent of the whorl from the peristome; 

 they are three in number, whereof the basal one is the largest, 

 that upon the parioties next in size, and the third (upon the outer 

 ■wall of the whorl above the keel) the smallest. 



The rich chestnut colour, the very glossy surface, and especially 

 the flat under-surface are the chief characteristic points of this 

 interesting species. 



108. Segmentika vicTOEi.a;, n. sp. (Plate YII. flgs. 11-13.) 

 Shell like S. australiensis, but not so flattened beneath ; last 



