216 G. W. BARTELMEZ 
cr. sul. 
ZS L fac. gang. 
2 ; 
ee 
X WAS wi \ 
Bee 
Cop. sul. 
Fig.9 A series to show the early development of the optic primordia corre- 
sponding to that of the otic anlagen. (See figure 2.) Here the optic primordium 
and otic anlagen are indicated by the solid color. a. H87—eight somites— 
section 28. b. Eternod ‘Du Ga’—nine somites—section 12. c¢. Wallin embryo— 
fourteen somites—section 24. d. H392—eleven somites—section 9, e. Pfannen- 
stiel II1I—fourteen somites—section 29. f. Mall no. 470—sixteen somites—slide 
1-4-5. 
