132 COMPARATIVE ANATOMY CHAP, n 



Literature. 



E. Haeckel. Die Gastrula und die Eifurcliuncj, in : Jenaischc Zeitsclirift. Bd 

 IX. 1877. 



F. M. Balfour. Comparative Embryology. 2 vols. London, 1880-81. 



A. C. Haddon. An Introduction to the Study of Embryology. London, 1887 (Tr.) 

 Compare further the bibliography on p. 117. 



