150 PROCEEDINGS OF THE MALACOLOGICAX SOCIETY. 



Other specimens refei'able to this species are found under largish 

 blocks of stone, near low-water mark, at Hardwicke Bay, Spencer Gulf. 

 They are somewhat broader than the type. The colours are the same, 

 except that they are paler throughout, with the whitish tints pre- 

 dominating more. The slits in one of these specimens stand : Anterior 

 valve 8, intermediate valves 1-1, posterior valve 7. 



/. Thomasi is undoubtedly very near to /. smaragdinus, but it seems 

 proper to signalize by a new name the real differences between the two 

 forms. It has much coarser girdle-scales than /. virgatus, Keeve. 



18. IscHNOcniToif (Ischnoeadsia) Jfov^-HoLLANDi^ (Reeve). 



Chiton NovcB-Hollandm (Grray MS.), Eeeve : Conch. Icon., sp. 142 ; 



Pilsbry, Man. Conch., ser. I, vol. xiv, p. 145, pi. xix, 



figs. 67-9. 

 Chiton [Lojjhjrus) Australis, Tenison-Woods: Proc. Roy. Soc. Tasmania, 



1877, p. 46 {7ion Sby.). 



This Chiton has only been recognized as a denizen of South 

 Australian waters during the last two years, although it had been 

 obtained at the Bluff, Encounter Bay, by two or three collectors some 

 time previously. So far as I know it has not been found at any 

 other station in this province. The Manual of Conchology gives 

 Adelaide, South Australia, but this is an error, for the coast-line in the 

 immediate neighbourhood of Adelaide is a long stretch of sandy beach, 

 and quite unsuited to the habits of the species under notice. /. Novm- 

 JIoUandicR is apparently a common species in Tasmania, where it has 

 been confounded with /. Australis (the New South Wales form) and 

 distributed by collectors as such. 



19. Callistochitox antiqutjs (Reeve). 



Chiton antiqims, Reeve: Conch. Icon., sp. 169; Pilsbry, Man. Conch., 

 ser. I, vol. xiv, p. 274, pi. lix, figs. 29-35. 



There can be no mistaking this beautifully sculptured Chiton, with 

 its malleated upper surface, acutely ribbed side slopes, prominently 

 costated end valves, and doubly costated lateral areas, all the 

 costations being sharply cut into well-defined rounded nodules, small 

 at their commencement and gradually increasing in size towards the 

 margin. "Australia" is the habitat given by Reeve for the type- 

 specimen, which in all probability was obtained at Port Jackson. 

 It was not known as a South Australian species to Angas when listing 

 our shells in 1864; but some three years later it was collected 

 by myself at Marino, on the east side of St. Vincent's Gulf, and 

 subsequently at Port Wilhmga. Mr. Matthews has lately collected 

 it on Yorke Peninsula. It also occurs at Port Molle, Queensland 

 (Coppinger). My largest New South Wales specimen measures 

 18x10 mm., in accordance with the dimensions given in the Manual 

 of Conchology ; but I have South Australian examples 22 mm. long. 

 It must be admitted, however, that they are not so presentable 

 as those from the eastern colonv. 



