BY C. HEDLEY. 197 



Thkaciopsis arenosa, n.sp. 

 (Plate ix., figs. 26-27.) 



Shell small, oblong, equilateral, anterior dorsal margin concave, 

 posterior dorsal margin convex, tapering more anteriorly than 

 posteriorly. Colour grey, with radiating and concentric lines of 

 pale yellow. Sculpture : the whole shell is densely covered with 

 small but sharp, elevated grains arranged radially. Height 2-9, 

 length 4-55 mm. 



Hah. — Sixteen miles east of Wollongong in 100 fathoms; 

 dredged by Mr. G. H. Halligan and self. 



Type. — To be presented to the Australian Museum. 



This species is represented only by a single left valve. The 

 sculpture, like sand-paper, is a remarkable character, and members 

 of this genus are usually inequilateral. Though more material is 

 requisite for a full description, these peculiarities should ensure 



Oardita dilecta. Smith. 



Smith, Chall. Rep. Zool. xiii. 1885, p. 213, pi. xv., f. 4. 



This pretty species extends to the waters of this State, for it 

 was included in the rich haul made by Mr. G. H. Halligan and 

 self in 100 fathoms, 16 miles east of Wollongong. It has not 

 been seen since its discovery in Bass Straits by H.M.S. 'Chal- 

 lenger,' thirty years ago. 



Zexatia victoria, Pritchard & Gatliff. 



Pritchard & Gatliff, Proc. Roy. Soc. Vic. n.s. xvi. 1903, p. 92, 

 pi. 15, f. 3. 



This species also reaches New South Wales. I saw it fre- 

 quently on the beach at Boyd Town, Twofold Bay, and have 

 taken a broken valve in Middle Harbour. It is evidently the 

 species which Angas reports* under the erroneous name of Z. 

 acinacies, Quoy &, Gaimard, from Botany Bay. Mr. O. Thiele 

 informs me that he observed it at Snake Island, Victoria. 



• Proc. Zool. Soc. 1867, p. 917. 



