INTESTINAL TRACT OF MAMMALS. 251 



Mitchell, P. Chalmers. — Observations on the Anatomy of tlie 



Shoe-bill {Balceniceps rex) and Allied Birds. P. Z. S. 



1913, p. 644. 

 Oppel, a. — Lehrbuch vei'gl. mikros. Anat. Wirbelthiere. Part II. 



1897. 

 Owen, R. — On the Anatomy of the Cape Hyrax. P. Z. S. 1832, 



p. 202. 

 Id. — Anatomy of Vertebrates. Vol. III. Mammals. London, 



1868. 

 Tullbeeg, Tycho. — Ueber das System der Xngethiere. Xov\ 



Act. Reg. Soc. Sci. Upsala, 1899. 

 WiLLEY, Arthur. — Convergence in Evolution. London, 1911 



