26 Frederick- Cha^mian : 



of small pittings or areolations. the margins of which tend to form 

 a rudely polrgonal network. These pittings are much finer an(J' 

 closer than seem to be indicated in the woodcut given bv Ameghino, 

 of Ceratodu< iheringi.x from the Upper Cretaceous of Patagonia. 

 The splenial portion at the base projects from the tooth for about 

 4.5 nmi., and is flange-like. At the junction of the tooth with 

 the splenial, the lower surface is rather deeply excavated. 



Dimension^.— IjQTxgth. of tooth when complete, about 35 mm. 

 Length of second anterior denticle from its junction with the base, 

 6 mm. Length of anterior denticle, approximately 17 mm. when 

 complete. Greatest height of tooth as distinct from the splenial 

 bone. 10 mm. 



OccurreiK-e. — Upper Cretaceous (opal deposits). Walgert. ' 

 Baradine, New South Wales. Collected and presented by T. C. 

 WoUaston, Esq. 



Bel-at ion ships. — A British form, Ceratodii^ di^auris. Agassiz,- 

 from the Rhaetic of Aust Cliff, shows, in the figure given by L. C. 

 Miall,^ four denticles, as in the present species. The denticles in 

 the specimen mentioned, however, are more trenchant than in the 

 present species. 



Ceratodus aru4. Smith Woodward.* sliows a nearer relationship- 

 than other described forms, in having four denticles, and in these 

 being comparatively short. 



An Upper Cretaceous species from Patagonia. C. iheringi, 

 Ajiiegliino.-' appears to be a palatal tooth. It has more salient den- 

 ticles, five in number, and. according to Ameghino. shows closer 

 alliance with the European mesozoic species than with the living 

 Australian C (yeoceratodtis) forateri. 



Dr. Emile Haug has described a Cretaceous species of Ceratodus 

 {C. africavu^.) from Djoua. near Timassanine. in the Sahara.^ 

 which differs from the Triassic European examples- in the presence 

 of crenulations upon the anterior side of the tooth, and of six ridges 

 instead of five, characters which approach those of the living lung- 

 fish. Cerafodvs (Xrorerafodus) forstrri. of Queensland. 



TTie surface character of the upper portion of the tooth <>f C. tpof- 

 Jasfoni bears a dose resemblance to the recent Cerafodv^. from 



I PnKHf. Unh-. La Phtto. Xo. f, 19M. p. 10, fijr. 1. 



e r«ss»us fossUes, Alias, vol iiL, ISSS, pi. \ix., fisj. 19. 



Z rSee Miall (Ceriitodiu parent:. Mi&ll non Ag^iaaz, fide Woodward and Siierbon. Brit. Fos;-. Ven. 

 IsSCi. p 36). Vul Soc. Mon., ISTs, pi. v.. fig. 7. 



4 Loc-, sui>ra cit., pd. L, fii^s- 1, la, h. 



5 Ijot: supra dt., j». 10. fi^. 1. 



6 C R. .\t-*d. S.-i., Piris, vol. ciLxxiiiL. 1904. p. 1S29. 



