436 E. I. WERBER 



Werber, E. I. 1915 Experimental studies aiming at the control of defective 



and monstrous development. A survey of recorded monstrosities 



with special attention to the ophthalmic defects. Anat. Rec, vol. 9. 



1916 a Blastolysis as a morphogenetic factor in the development of 



monsters. Proc. Amer. Ass. Anat. in Anat. Rec, vol. 10. 



1916 b Experimental studies aiming at the origin of monsters. I. 



An etiology and an analysis of the morphogenesis of monsters. Jour. 



Exp. Zool., vol. 21. 

 Wetzel, G. 1895 Uber die Bedeutung der zirkularen Furche in der Entwick- 



lung der Schultze'schen Doppelmissbildungen von Rana fusca. Arch. 



f. mikrosk. Anat., Bd. 46. 



1896 Beitrag zum Studium der kiinstlichen Doppelmissbildungen 



von Rana fusca. Inaug.-Diss. 

 Wilder, H. H. 1904 Duplicate twins and double monsters. Am. Jour. Anat., 



vol. 3. 



1908 The morphology of Cosmobia. Speculations concerning the 



significance of certain types of monsters. Am. Jour. Anat., vol. 8. 

 Wilson, E. B. 1893 Amphioxus and the mosaic theory of development. Jour. 



Morph., vol. 8. 



PLATE 1 



EXPLANATION OF FIGURES 



14, 15 and 16 Transverse sections through 'parasitic double monster' of 

 figure 11. L., lens.; I., small lentoid body; b., brain; e., anterior-most part of 

 eye; d.e., dissociated epidermis; o.c, optic cup; d.o., dissociated optic cup; 

 d.m., dissociated epithelium of mouth; y., yolk. X 105. 



