76 



three original specimens dredged by Dr. J. C. Verco, now 

 in Dr. Torr's collection, is labelled "Spencer Gulf." Messrs. 

 Gatliff and Gabriel have now added Port Phillip Heads, 

 Victoria, as a locality (see previous reference). At present 

 our knowledge of this species is limited to four specimens. 



Remarks. — Under this heading in the original descrip- 

 tion the statement in the second line, "the first valve being 

 the broadest," should have read "the first median valve 

 being the broadest." A reference to the measurements given 

 above will clear this up. 



The great breadth, in proportion to its short longitudinal 

 length, of the anterior valve easily distinguishes this species 

 from any other known form. 



I am presenting type to the South Australian Museum. 



Stenochiton juloides, Adams and Angas (Proc. Zool. Soc, 



1864, p. 193; op. cit., 1865, pi. ii., fig. 15). 



Pis. xiii. and xiv., figs. 3, 8, 9, and 10. 



As no description, I believe, of this species occurs in 

 any Australian literature, it may be well to redescribe it here. 



General appearance. — Shell very solid and elongated, 

 sides much curved, the arch being continued evenly from 

 the girdle right over the dorsal area. Width of shell, one- 

 seventh of total length. The whole shell highly polished. 



Colour and markings. — Colour dark chocolate, merging 

 in the pleural areas into maroon. (Col. Plates Soc. Francaise 

 des Chrysanthemistes, 343, No. 4, and 341, No. 3). Many 

 specimens are .much flecked and streaked with grey dashes, 

 giving a grey-chocolate effect. 



Inside colour. — Anterior valve bluish-grey, others 

 whitish-grey with the brown of outer shell showing through. 



Anterior valve. — Strongly convex, considerably longer 

 than wide, unsculptured except for several shallow sulci fol- 

 lowing the growth-lines, highly polished, inside many slits, 

 counted 17, which are continued in grooves to the apex; the 

 pitting of these grooves is only just discernable under a 

 2-inch objective and eye piece. 



Posterior valve. — Mucro posterior (Carpenter states 

 median), the anterior portion of valve quite smooth and 

 rounded longitudinally, forming a V-shaped area the full 

 width of the valve at the suture (in the specimen described 

 5'5 mm. wide and a length to the mucro of 5 mm.). The 

 posterior portion is highly polished and unsculptured, except 

 for a number of concentric sulci following the growth -lines. 

 The posterior area where it abuts on the anterior V-shaped 

 portion is highly raised, the anterior margin forming a 

 rounded diagonal ridge ; this ridge is formed by a deep sulci 



