Lect. II.] THE CEEATODUS A GIFT OF PROVIDENCE. 27 



people who do this vain thing are emiihiting the fame of 

 the renowned Mrs Partington, endeavouring with her 

 mop to keep back the Athantic waves. 



Whatever the ftimous Triassic jaw of Microlestes may 

 turn out to be, it must not be left unnoticed that its 

 owner co-existed with a fish (Ceratodus), that still co- 

 exists with Monotremes and Marsupials in the Australian 

 region. The living Ceratodus is a waif or stray from 

 a nearly lost order of fishes — the Dipnoi, or double- 

 breathers — fishes that possess both gills and lungs, and 

 thus enjoy both aquatic and aerial respiration. Now 

 such fishes as this Australian Ceratodus, as the African 

 Protopterus, and as the American Lepidosiren, may have 

 co-existed with the Ganoids, or fishes with enamelled 

 armour, through much of the Primary period. Could this 

 be proved, we should have a capital generalised stock, 

 existing long before the period of the Trias, from which 

 to derive all the lung-1jreathing forms, whether of Am- 

 phibia, Reptiles, Birds, or Mammalia. Indeed, Professor 

 Huxley is very bold in this matter, and suggests that 

 Ceratodus is a special gift of Providence, kept for these 

 latter days, to rebuke and convince the gainsayers of the 

 truth of Darwinism. 



I cannot go into details ; we walk here by faith as 

 well as by sight. Imagine some low, ancient, simple 

 form of fish, that did, by metamorphosis, become a 

 creature as high as the Ceratodus. And that you may 

 be able to see this hypothetical fish ascend, during its 



