101 



Genus Nacella, Schumacher. 

 N. parva, Angas. 

 Hah. — One example dredged dead at 62 fathoms N.W. of 

 Cape Borda: several found in shell sand, Guichen Bay, which 

 is its most easterly known station. 



N. crebristriata, Verco. 



Hah. — The type locality was not exactly known, but was 

 judged to be Moonta Bay. I have since taken several ex- 

 amples in shell-sand at Guichen Bay. There are variations 

 from the type. The anterior slope may be sub-convex, or it 

 may be slightly excavated immediately below the apex. Some 

 are more compressed laterally than the type, others tend 

 more to an elliptical outline. There may be about sixteen 

 equidistant pink radii, or the shell may be uniformly of a 

 light pink tint. 



N. stowae, Verco. 



Hah. — Guichen Bay beach, in shell-sand. No variations 

 from the type. 



Family ACM^IDvE, Philippi. 



Genus Acm.ea, Eschsholtz. 



A. fiammea, Quoy k Gainiard. 



Patelloidea fiammea, Q. & G., Voy. de TAstrolabe, Zool., voL 

 iii.. 1834, p. 534, pi. Ixxi., f. 15 to 24. 



My observations on this variable shell in Trans. Roy. 

 Soc. South Australia, vol. xxx., 1906, p. 212, were almost 

 entirely based on dredged shells. A collection since gathered 

 from the rocks at Robe, Beachport, and MacDonnell Bay 

 enables me to add something further. As a rule the exposed 

 shells are much more eroded, and their ribs are ruder and 

 less numerous, and they are of the A. jarksoniens/s, Reeve, 

 form rather than of the A . cri/cis, Ten. Woods. Many of these 

 were much narrowed anteriorly, so as to be really oval or 

 egg-shaped instead of uniformly roundly elliptical. Some of 

 the smaller individuals tend also to be pyramidal rather than 

 conical, with four obsolete angles occupying the situation of 

 the intervals between the arms of the Maltese cross. None 

 were found with radial ribbing so fine as presented on some 

 of the dredged specimens. 



In most the cross was plainly visible, or indistinctly when 

 held up to the light. One showed the anterior and both late- 

 ral arms fused into one mass, and the posterior arm very 

 broad, so as to give a quite black shell with two narrow dead 

 white radii at the postero-lateral parts. Another was a 

 black shell with four narrow white radii. Another had five 



