Lect. II.] ANCESTORS OF THE MAMMALIA. 47 



mucli as, or more than, the skull of the Ornitho- 

 rhynchiis differs from that of a Man. 



We may suppose the ancestors of the original teatless 

 mammals (Prototheria) to have been something like, and 

 not much higher than, the larva of the nailed Toad, and 

 that these underwent an amount of transformation, 

 during an active out-of-door life, equal to that under- 

 gone by the existing type. Afterwards, by little and 

 little, such Prototheria may have improved themselves 

 into higher and still higher ty]^)es ; they have had plenty 

 of time for such changes. 



ADDENDUM TO LECTURE II. 



Bibliography: Eeferences to Works and Papers treating 

 OF THE Ornitliorhynclius and Echidna. 



Armit, Captain William E., E.L.S., "Ilotes on the Presence of 



Tacliijglossus and Ornitliorhynclms in JSTorthern and J^ortli 



Eastern Queensland," Proceedings of the Linnean Society^ 



Zoology, vol. xiv., 1879, pp. 411-413. 

 Bennett, Dr George, E.L.S., F.Z.S., &c,, Gatlierings of a Naturalist 



in Australia. London : John Van Voorst. 1860. 

 Flower, Prof. W. H., LL.D., F.R.S., An Lifrodnction to the 



OsteoJogy of the Mammalia. London: Macmillan & Co. 1876. 

 Article " Mammalia " in the Encyclojpcedia Britannica, 9th 



edit., vol. XV., pp. 377-378. 

 Huxley, Prof. T. H., LL.D., Pres. K.S., A ManiiaJ of the Anatomy 



of the Vertehrated Animals, pp. 319-323. London: J. & A. 



Churchill. 1871. 



