94 



Western Australian polyplacophora. 



By W. G. Toer, M.A., B.C.L. (Oxon.), LL.D. 

 (Dublin and Adelaide). 



[Read October 12, 1911.] 



Plates XXIV. and XXV. 



In the September, 1910, number of the Proceedings of 

 the Malacological Society of London, vol. ix., part 3, p. 153, 

 Mr. Tom Iredale has some "Notes on Polyplacophora, chiefly 

 Australian." On p. 159, Mr. Iredale says: "I conclude that 

 the chiton fauna of Western Australia will be of a most 

 interesting nature." 



Through the courtesy of Dr. J. C. Verco, the President 

 of the Royal Society of South Australia, I was able during 

 the Christmas vacation of 1910-11 to make a fairly thorough 

 exploration of the south coast of Western Australia from 

 Esperance to Albany, and the west coast as far north as 

 Fremantle. 



The places visited were Esperance, Hopetoun, Albany, 

 Ellenbrook and Yallingup (south of Cape Naturaliste), Greo- 

 graphe Bay, Rottnest Island, and Fremantle Harbour. 

 With the assistance of Mr. Hedley, conchologist (of the 

 Australian Museum, Sydney), and Mr. Basset Hull, of Syd- 

 ney, I have been able to identify twenty-three species of 

 Western Australian polyplacophora similar to South Aus- 

 tralian species and nine others, seven of which I take to 

 be new. 



As Mr. Iredale suggests in the paper mentioned, the 

 list contains representatives of the Adelaidean region. At 

 least fifteen of the identified species are found in his Ade- 

 laidean list, one is classified as Solanderian, two are in the 

 Peronian, and three are in the "Doubtful Position" list. 

 The seven new species will probably represent the Autochth- 

 onian element to which Mr. Iredale refers. 



The small rise and fall of the tides (not more than 2 or 

 3 ft.) on the visited parts of the Western Australian coast 

 make chiton hunting much more precarious than in South 

 Australian waters. While a large number of South Aus- 

 tralian chitons are found in Western Australia, yet there are 

 some striking diiferences. 



I have traced Plaxiphora albida, Blain, locally known as 

 P. petholata, Sby., all round the South Australian coast 

 from MacDonnell Bay to Murat Bay, a distance of nearly a. 



