146 



Many scores of specimens are in my cabinet from both 

 Gulf St. Vincent and Spencer Gulf, also from Hopetoun and 

 Albany, in Western Australia. I have dried specimens 

 46 mm. long and 22 mm. broad. 



14. Ischnochiton variegatus, Adams and Angas, 1864. 



Lepidopleurus variegatus, H. Adams and Angas. Proc. Zool. 

 Soc, 1864, p. 192; Pilsbry, Man. Conch., ser. i., voL xv., p. 102. 



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

 vol. ii., part 4, April, 1897, p. 146. 



This species is found in Spencer and St. Vincent gulfs. 

 It will probably be classed under I. crispus, which it closely 

 resembles. Pilsbry has no plates of this variety in his 

 Manual, and the description given would equally apply to 

 /. crispus. Bednall says it attains a length of two-thirds of 

 an inch. I have a number of specimens from the coasts of 

 Yorke Peninsula, Port MacDonnell, Cape Jaffa, and Marino. 

 It is probably a cream-coloured variety of crispus. 



15. Ischnochiton sulcatus, Quoy and Gaimard, 1834. 



Chiton sulcatus, Quoy and Gaimard, Voy. "Astrolabe," Zool., 

 1834, vol. iii., p. 385. 



C. decussatus, Reeve, Conch. Icon., 1847, pi. xviii., fig. 107. 



C. castus, Reeve, op. cit., pi. xxii., fig. 145. 



Lepidopleurus speciosus, Adams and Angas, P.Z.S., 1864, 

 p. 192; 1865, p. 187. 



Gymnoplax urvillei, Rochebrune, Bull. Soc. Philom., Paris, 

 1880-1, p. 121. 



Ischnochiton sulcatus, Quoy and Gaimard : Pilsbry, Man. 

 Conch., 1893, ser. i., vol. xiv., p. 138; Iredale, Proc. Mai. Soc, 

 London, vol. ix., part 2, June, 1910, p. 91. 



I. decussatus, Reeve: Bednall, Proc. Mai. Soc, London, 

 1897, vol. ii., p. 146. 



The most beautiful of the South Australian Ischno- 

 chitons may be easily distinguished by being broader in pro- 

 portion to its length than the majority of I schno chitons. It 

 favours the edges of rocks, and is often found on top of stones 

 and on the razor-like bivalve, Pinna inermis. The colours 

 are very various — blue-green, rich brown, cream with brown 

 dorsal areas, ochreous-yellow with splashes of purple, straw- 

 colour with dark-brown splashes, brown and green with cream- 

 white dorsal areas, and uniformly cream. I have dried speci- 

 men, 46 mm. long and 27 mm. broad. Juveniles may be 

 easily distinguished by the regular pustules in the anterior 

 and posterior valves and the lateral areas of the median 

 valves. They are common in Spencer and St. Vincent gulfs, 

 Streaky Bay, and West Coast. 



