PLATE 4 



EXPLANATION" OF FIGURES 



23, 24, 25, 26 and 27 Transverse sections through dwarfed double embryo of 

 figure 12. 6 1( brain of the larger component; b 2 . brain of the smaller component; 

 h, and h lenses in anterior-most, greatly dissociated part of the eye of the larger 

 component; I., lens (smaller component); e., eye; d.e., dissociated epidermis; 

 7n.o., medulla oblongata of smaller component; e.v., rudimentary ear vesicle; 

 o.c, posterior-most, greatly dissociated part of the optic cup of the smaller 

 component; p., plasma in pericardial vesicle; /., tail of smaller component. 

 X 105. 



442 



