34 SIRENOID AND CROSSOPTERYGIAN GANOIDS. 



Discoveries of fossil teeth during the last three decades, however, have much 

 extended our knowledge of the geographical range of Ceratodus during successive 

 geological periods. Triassic and Rhsetic species are now known, not only from Europe 

 and India, but also from South Africa. 1 During the Jurassic period the genus was 

 represented in Europe (see p. 32), North America, 2 and Australia. 3 Teeth of Cretaceous 

 age have been found in Central Africa* and Patagonia; 6 and evidence of a supposed 

 extinct species occurs in the comparatively modern river-deposits of Queensland. 6 It is 

 therefore probable that Ceratodus was nearly cosmopolitan during the greater part of the 

 Secondary Epoch, and became restricted to the Australian region only during Tertiary 

 times. 



1 Ceratodus capensis, A. S. Woodward, 'Ami. and Mag. Nat. Hist.' [6], vol. iv (1889), p. 243, 

 pi. xiv, fig. 4; Stormberg Beds, Smithfield, Orange Colony. — Ceratodus Kannemeyeri, H. G. Seeley, 

 ' Geol. Mag.' [4], vol. iv (1897), p. 543, with fig. ; Stormberg Beds, Kraai Fontein, Cape Colony. 



2 Ceratodus Ouentheri, O. C. Marsh, ' Amer. Journ. Sci.' [3], vol. xv (1878), p. 76, with fig.; 

 Upper Jurassic, Colorado. 



3 Ceratodus avus, A. S. Woodward, ' Ann. and Mag. Nat. Hist.' [7], vol. xviii (1906), p. 2, pi. i, 

 fig. 1 : Lower Jurassic, Cape Patterson, Victoria, Australia. 



* Ceratodus qfricanus, E. Haug, ' Comptes Eendus,' vol. cxxxviii (1904), p. 1529, and in Foureau, 

 'Docum. Sci. Miss. Saharienne,' vol. ii (1905), p. 819, pi. xvii. figs. 1 — 5; Bjoua, Timassanine, 

 Sahara. Also C. minutus, Haug, torn, cit., 1905, p. 821, pi. xvii, fig. 6. 



5 Ceratodus Iheringi, F. Ameghino, ' Public. Univ. La Plata,' no. 2 (1904), p. 10, fig. 1. 



6 Ceratodus Palmeri, Gr. Krefft, 'Nature,' vol. ix (1874), p. 293. See also W. B. Clarke, ' Mines 

 and Min. Statistics N. S. Wales' (1875), p. 205, and C. W. Be Vis, ' Proc. Roy. Soc. Queensland,' 

 vol. i (1884), p. 40. 



