XIII THE SKELETON 245 



REFERENCES 



Parker, W. K. On the Structure and Development of the Skull of 

 the Common Frog, Phil. Trans., Vol. 161, 1871. On the Structure and 

 Development of the Skull in the Batrachia. Phil. Trans., Vol. 166, 

 part I, 1 881. 



Parker and Bettany. The Morphology of the Skull, London, 1887. 



