242 



I therefore consider that we are justified in retaining C. oculatus, Q. and G., 

 as a good species. 



Description. — The sculpture of this species is composed entirely of longi- 

 tudinal ridges, the first three valves are circular, broad, and imbricating; all 

 the rest, in adult shells, are narrow and more or less spaced. 



Girdle. — The girdle is handsomely banded and the spicules are dense, 

 short, stout, and have rounded apices; in this respect it is the only species that 

 seems to approach the spiculose character of Lamarck's C. laevis. 



I have two juvenile specimens given to me as from Torres Strait, by Major 

 Dupuis, that quite possibly belong to this species, but determination is difficult, 

 as all the spicules have been lost. These are the only specimens I have seen 

 that are strictly Australian in origin. While we were unable to locate Quoy 

 and Gaimard's type in the Paris Museum, it is just possible that the shell 

 described by Rochebrune, under the name C. montanoi, may have been their 

 actual type, for he was not adverse to doing such, for, as I have before shown, 

 Rochebrune certainly gave a new name to Blainville's type of Chiton longicymba. 



Cryptoplax burrowi. Smith, 1884. 



(Chitonellus burrowi, Smith, Zool. Coll. H.M.S. Alert, p. 85, 1884; Chitonellus 

 larvaeformis, Blainville of Reeve, Conch. Icon., f. 3, 1847; Crvptoplox burrowi, Haddon, 

 Chal. Polyplac, p. 42, pi. 3, f. 11 a-m; Pilsbry, Man. Con., vol. 15, p. 54, 1892.) 



Quoting from Pilsbry : "This curious species is known by the small size of 

 the valves, the remoteness from one another of the fourth, fifth, and sixth, and 

 the excessively short and densely packed spines on the mantle." Reeve's figure 

 is excellent, but his habitat of Port Adelaide is, of course, a myth ; but the 

 specimen recorded as having been taken at Port Molle, in Queensland, is 

 probably authentic. I did not see this species in the collections in the British 

 Museum, but we may have overlooked it. 



Summary List of Australian Cryptoplax. 



L Cryptoplax striatus, Lamarck. South Australia and Victoria, 



la. „ striatus, var. gunni, Reeve. Tasmania, 



lb. „ striatus, var. zvesternensis, Ashby. Western Australia. 



n. „ laevis, Lamarck. Locality and identification doubtful, 



in. „ iredalei, Ashby. South Australia and Tasmania. 



IV. ,, rostratus, Reeve. New South Wales and Queensland. 



V. „ oculatus, Quoy and Gaimard. Queensland. 



VI. ,, burrowi. Smith. Queensland. 



VII. „ hartmeyeri, Thiele. Western Australia. 



VIII. „ michaelseni, Thiele. Western Australia. 



A total of eight species and two varieties. 



DESCRIPTION OF PLATES XVI. to XIX. 



All reproductions from photographs by E. Ashby. 



Plate XVI. 

 Fig. 1. Lepidopleiirus liratus. Ad. and Ang. From South Australia. 

 „ 2. „ profundus, Ashby. Type. From South Australia. 



„ 2a ,, profundus. From South Australia. Median valve, edge on. 



„ 3. „ columnarius, Hed. and May. From Tasmania. 



„ 3a. „ columnarius. Median valve, edge on, marked co-type. 



