148 



in the pleural area are, under a J-in. lens, arrow-shaped, with 

 the point towards the dorsal area. 



Mr. Matthews has kindly sent me a very fine specimen, 

 24 x 14 mm., which I take to be I. wilsoni. It has not the 

 rosy-pink of the type, but the splashes of grey-brown and 

 white correspond with Syke's drawing. The girdle scales are 

 black, amber, and pearly-white, the rich brown splashes pre- 

 dominating. As far as I can decide with an undissected 

 specimen, the anterior valve has nine and the posterior valve 

 eight slits. The striations of the girdle scales are very dis- 

 tinct, four to seven striae on each scale. 



18. Ischnochiton smaragdinus, Angas, 1867. 



Lophyrus smaragdinus, Angas, Proc. Zool. Soc, 1867, p. 115; 

 Pilsbry, Man. Conch., ser. i., vol. xiv., p. 137, vol. xv., pi. xv., 

 fig. 27. 



Lepidopleurus smaragdinus, Carpenter, MS. 



Ischnochiton smaragdinus, Bednall, Proc. Mai. Soc, London, 

 vol. ii., part 4., April, 1897, p. 148. 



I. (Haploplax) smaragdinus, Angas : Pilsbry, Proc. Acad. 

 Nat. Sci., Philad., 1894, p. 72. 



The drawing of this shell in Pilsbry's Manual is very 

 unsatisfactory. Both Angas' and Carpenter's descriptions 

 seem incomplete. This shell may be distinguished by the 

 blue-green spots on an olive-brown ground and the very pearly 

 scales on the girdle. It is generally found in deeper water 

 than the majority of I schno chitons. It has the blue spots 

 of I. lentiginosus of New South Wales, but it is not so carin- 

 ated nor are the lateral areas so distinct as in /. lentiginosus. 

 I have specimens from Yankalilla, Normanville, Second Val- 

 ley, Aldinga, Marino, and elsewhere. It is exceedingly com- 

 mon on the north-west coast of Tasmania, where it is found 

 in shallower water than in South Australia. I have con- 

 siderable difficulty in separating this species from Ischno- 

 chiton resplendens, Bednall and Matthews, Proc. Mai. Soc, 

 London, vol. ii., part 2, June, 1906. 



19. Ischnochiton virgatus, Reeve, 1848. 



Chiton virgatus. Reeve, Conch. Icon., sp. 192; Pilsbry, Man. 

 Conch., ser. i., vol. xiv., p. 78. 



Trachydermon virgatus, Reeve: Carpenter, MS., p. 22. 



Ischnochiton virgatus, Reeve: Carpenter, MS., p. 106; Bed- 

 nall, Proc Mai. Soc, London, vol. ii., part 4, April, 1897, p. 148. 



This very pretty diminutive chiton, so ably described by 

 Mr. Bednall, loc. cit., has been found all along the South 

 Australian coast from Port MacDonnell to St. Francis 

 Island. I have specimens from nineteen different places, in- 



