161 



A. (Loboplaxj variabilis, Adams and Angas : Bednall.Proc 

 Mai. Soc, London, vol. ii., part 4, April, 1897, p. 156; Hedley 

 and Hull, Records Australian Museum, vol. xii., No. 4, 1909, 

 p. 266. 



This is the most widely distributed of all South Australian 

 A cantho chitons. I have found it all around the coast from 

 Port MacDonnell to St. Francis Island. It is found on the 

 South-East coast, St. Vincent and Spencer gulfs, and on the 

 West Coast as well as on Kangaroo Island. I have specimens 

 from twenty-three different places. The pinnatifid appear- 

 ance of the dorsal area and the very tiny spicules at the 

 sutures, sometimes only horny protuberances, easily differ- 

 entiate this species from other Acanthos. It assumes every 

 variety of shade and colour from a creamy-white to almost 

 black, greens generally predominating. Lighter - coloured 

 varieties are plentiful on Kangaroo Island and the west coast 

 of Yorke Peninsula. 



In young specimens the girdle of the Acanthos is very 

 small, but when full-grown it has a large fleshy girdle, often 

 twice as wide as the tegmentum. If not kept in spirits this 

 girdle shrinks up considerably. 



47. Acanthochites crocodilus, Ton* and Ashby, 1898. 



Acanthochites crocodilus, Torr and Ashby, Trans. Roy. Soc, 

 S.A., 1898, p. 216, pi. vi., fig. 2. 



Two specimens were found at a very low tide at Marino, 

 one valve was taken by Mr. Klem at Corney Point, and Mr. 

 Hedley, Records Aus. Mus., vol. vii., No. 2, 1908, Hedley 

 and May, reports having taken it off the coast of Tasmania. 

 May and Torr, Proc. Roy, Soc, Tasmania, 1912, pp. 35, 36, 

 say this is not crocodilus. 



The remarkably foliated appearance of the dorsal area 

 and the shagreened pustules on the latero-pleural area make 

 it easy to distinguish this rare species. 



48. Acanthochites cornutus, Torr and Ashby, 1898. 



Acanthochites cornutus, Torr and Ashby, Trans. Roy. Soc, 

 S.A., 1898, p. 217, pi. vi., fig. 3. 



This is evidently a deep-water species. It was dredged 

 by Dr. Verco in 14 fathoms off Ardrossan. Mr. A. R. Riddle 

 took one at Wool Bay. Specimens have been taken at 

 Marino, Norman ville, and St. Francis Island. 



Its pinnatifid dorsal area, decided carination, and regular 

 rows of pustules are its distinguishing features. Mr. Hedley 

 found eyes on the dorsal area of A. cornutus. He used J-in. 

 lens. 



