148 
in the pleural area are, under a }-in. lens, arrow-shaped, with 
the point towards the dorsal area. 
Mr. Matthews has kindly sent me a very fine specimen, 
24x14 mm., which I take to be Z. 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 striz on each scale. 
18. Ischnochiton smaragdinus, Angas, 1867. Flap 
Lophyrus smaragdinus, Angas, Proc. Zool. Soc., 1867, p. 115; 
Saw Man. Conch., ser. i., vol. xiv., p. 187, vol. xv., pl. xyv., 
Z. 27: 
Lepidopleurus smaragdinus, Carpenter, MS. 
Ischnochiton smaragdinus, Bednall, Proc. Mal. 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 Zschnochitons. 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 7. 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 Zschno- 
chiton resplendens, Bednall and Matthews, Proc. Mal. Soc., 
London, vol. ii., part 2, June, 1906. 
19. Ischnochiton virgatus, Reeve, 1848, 4 G6 
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. Mal. Soc., London, vol. ii., part 4, April, 1897, p. 148. 
This very pretty diminutive chiton, so ably described by 
Mr. Bednall, /oc. 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- 
