702 STUDIES ON AUSTRALIAN MOLLUSCA, 



COLUMBELLA FLEX A, n.Sp. 



(Fig. 25.) 



Shell small, clathrate, bluntly fusiform, a little contracted at 

 the base, polished, semi-diaphanous but rather solid. Colour pale 

 brown, suddenly changing to darker on the base. 

 Including a smooth globose, two-whorled proto- 

 conch, the whorls are five, flattened, parted by a 

 channelled suture, the last twice the length of the 

 spire. Sculpture : about twenty close narrow 

 regular sharp longitudinal ribs descend the shell 

 perpendicularly, continuing after each sutural gap 

 from whorl to whorl and vanishing graduall}' on 

 the base; the interstices of these longitudinals 

 Fig. 25. g^j,g interwoven by finer, closer and less prominent 

 spiral cords, which extend past the longitudinals to the anterior 

 extremity, numbering 14 on the last whorl and 5 on the spire. 

 Aperture slightly ascending, not thickened externally, narrow, 

 perpendicular, denticulated within by several (3-5) entering 

 ridges. Canal short, recurved. Length 4*5, breadth 1 7 mm. 



Hah. — Ladies' Hall Beach, near South Head, S3^dney Harbour; 

 t\vo specimens (H. L. Kesteven). 



Ty pe to be presented to the Australian Museum. 

 To the kindness of H. L. Kesteven I owe both the opportunity 

 of describing this species and the excellent drawing which illus- 

 trates it. The present is readily known from any other small 

 Australian Columhella by the reticulate sculpture. 



Haliotis semiplicata, Menke. 



Menke, Moll. Nov. Holl. Spec. 1843, p. 32. 



This rare West Australian shell has not been recognised by 

 any succeeding writer. Tate in his review of Menke's shells 

 passes it without comment.* Pilsbry consigns it to the list of 

 unidentified species, f 



* Tate, Proc. Linn. Soc. N.S.W., vi., p. 401, 1882. 

 t Pilsbry, Man. Conch, xii., 1890, p. 126. 



