ANNIVERSARY ADDRESS-. 9 



the Curator of -which institution it was first described. Dr. 

 GKinther, in his more elaborate description, does full justice to 

 the brief notice of the Ceratodus and the correctness of the 

 alliance to Lepidosiren, pointed out in that notice by Mr. Kreiffc 

 who by good management obtained it for the Museum. The 

 importance of this genus, of which another species, C. Miolepis, 

 has been found since, resembling in its teeth one of the Secon- 

 dary forms, may be gathered from the following remark by Dr. 

 Giinther : — "In Ceratodus we have now found a genus which, as 

 far as evidence goes, persisted unchanged from the Mesozoic era; 

 and in the Sire?iidce, a family the nearest ally of which lived in 

 the Paleozoic epochs." [Phil. Trans., Part II, 1871, p. 561.] 



It is an extraordinary fact that we have living in Australia 

 numerous species belonging to the vegetable and animal 

 kingdoms which represent genera of vast antiquity in the 

 geological scale of life, and recent investigations have corrected 

 some of the errors which have prevailed. Till recently the 

 Ceratodus was considered to be a shark ; and Mr. Tate, who has 

 published an excellent paper on the Secondary fossils of South 

 Africa (Q. J., Gr. S., Peb., 1867), speaking of the Order Cijea- 

 dacece during Jurassic times, says the Order has only continued 

 to exist in South Africa, forgetting that it has representatives 

 both recent and fossil in Australia. 



Among the curious things shown to me onboard the "Challen- 

 ger," there were representatives of Pentacrinus and other 

 Cretaceous genera, as well as a variety of novel organisms, for 

 the descriptions of which we must wait till the future publications 

 of Professor Thomson shall have placed his illustrations of them 

 before the world. 



The diagrams exhibited in 1874 to this Society were confined 

 to the Atlantic, as the " Challenger" had not then completed its 

 work in the Pacific, nor had the portion belonging to the ocean 

 space between Sydney and New Zealand (in which we are all 

 interested in relation to submarine communication) been then 

 sounded in its greater depths. The view which was formed of 



