BY C. HEDLEY. 167 



described in albanensis) by the adult and the shell at once com- 

 mences to widen axia'.ly ; viewed either from above or beneath, 

 the smoother plane embryonic shell is seen as the flat floor of the 

 spiral or umbilical pit. Sculpture : the last whorl is adorned 

 with 150 sharp erect straight costse, which are seen to stand out 

 in profile on the periphery like the teeth of a circular saw, they 

 are directed straight across the whorl from the spiral to the 

 umbilical sutures and may be likened to the lines of longitude on 

 a terrestrial globe. The secondary sculpture varies upon different 

 parts of the shell, that sketched in the accompanying illustration 

 is selected from the umbilical wall of the last revolution. U[)on 

 the spire two or three raised hair-lines parallel to the costse occupy 

 the intercostal spaces, at right angles similar hair-lines cross both 

 these and the costte, producing a reticulated appearance. Towards 

 the periphery these spiral lines grow faint, while the intercostal 

 lines multiply to half-a-dozen, within the umbilicus the transverse 

 lines diminish and the spiral sculpture assumes the supremacy. 

 Umbilicus cup-shaped, profound, exposing every revolution, a 

 third of the shell's diameter in width. Aperture perpendicular, 

 crescentic, peristome straight, sharp, scarcely reflexed on the 

 columellar margin, projecting at the periphery past an imaginaiy 

 line drawn from insertion to insertion. Callus smooth, shining, 

 thick, semitransparent, quite burying the overtaken costfe, pro- 

 jected on the penultimate whorl in advance of the peristome. 

 Diam. maj. '2^, min. 2\, alt. Ijmra. 



T y p e in the collection of C. E. Beddome, Esq., R.N. 



H a b. — Gad's Hill and Mount Bischofi", Tasmania (Beddome) ; 

 occurred under timber. 



var. alba, var.nov. 



Entirely hyaline-white. 



Occurred with the above. 



C. BiscHOFFENSis, Beddome (1879). 

 (Plate I. figs. 1, 2, 3, 4.) 

 D e s c r"- — Monograph of the Land Shells of Tasmania, p. 39 ; 

 Proc. Roy. Soc. Tasmania, 1879, p. 23. 



