101 



me from Eyre Patch, Western Australia, not far from the 

 South Australian boundary. It is often found high and dry 

 in crevices of rocks at and above high-water mark. It is 

 remarkable that no specimens have been discovered in South 

 Australian waters when it is so common in Western Aus- 

 tralia. It occupies a similar position in Western Australia 

 to that taken by Plaxiphora albida in South Australia. 



The figure in Pilsbry, vol. xiv., plate 53, figs. 36-40, 

 shows the concentric marking and the beaks of the valves 

 very distinctly. My specimens are nearly all much worn, 

 and only a few valves retain the beak ; the more perfect 

 specimens show both the beak and rows of concentric polished 

 pustules on the anterior valve, radiating from the apex. 



25. Onithochiton quercinus, Gould, 1846. 



Chiton quercinus, Gould, Proc. Bost. Soc Nat. Hist., 1846, 

 -vol. ii., p. 142; U.S. Expl. Exped. Moll., p. 312, figs. 437, 437a: 

 Otia, Conch., p. 3. 



C. (Onithochiton) quercinus, Gould, Otia, Conch., p. 242. 



C. Incii, Reeve, Conch. Icon., 1847, No. 94. 



Onithochiton rugulosus, Angas, P.Z.S., 1867, pp. 115, 223. 



0. Incii, Angas, P.Z.S., 1867, p. 223. 



0. Lyelli (non Sow.), Pilsbry, Man. Conch., vol. xiv., p. 247. 



0. quercinus, Gould; Pilsbry, Man. Conch., vol. xiv., p. 248. 



0. rugulosus, Angas; Pilsbry, Man. Conch., vol. xiv., p. 

 -249; Proc. Acad. Nat. Soc, Phil., 1894, p. 88. 



0. Incii, Reeve; Thiele, Zoologica Chim., Heft, lvi., p. 99. 



0. quercinus, Gould; Iredale, Proc. Mai. Soc, London, vol. 

 ix., part 2, June, 1910. 



Specimens of this very beautiful chiton were taken at 

 Esperanoe. Albany, Ellenbrook, and Rottnest Island. On 

 -the outlying reefs at Rottnest they could be seen crawling 

 over the reefs very energetically. Gould's type specimen was 

 a small one — length, 22 mm. ; breadth, 15 mm. I have a 

 dried specimen, slightly curled, taken at Port Esperanoe — 

 length, 52 mm. ; breadth, 23 mm. It is beautifully coloured. 

 Those found on exposed rocks were covered with foreign 

 matter. I have to thank Messrs. Hedley and Hull for the 

 identification of this species. 



Unfortunately I have not had access to a description of 

 Onithochkon Scholvieni, Thiele, Zool. Chun. 1909. Heft, 

 lvi., p. 99. Mr. Iredale says in the paper quoted that the 

 specimens in the British Museum are labelled "West Aus- 

 tralia." He thinks that is correct. My specimens of O. 

 quercinus vary considerably. It is possible that I may be 

 able to place some of them with Scholvieni. 



