CHORIO-ALLAXTOIC GRAFTS. 289 



and the inner nuclear layer is an inner molecular layer, very 

 granular in appearance and containing only a very few scattered 

 nuclei which have failed t<> associate as yet with either of the 

 adjoining layers. The inner nuclear layer i> nearly three times 

 as wide as the molecular layer and is very heavily nucleated. 

 Separating thi- from the miter nuclear layer is the outer molecular 

 layer, also free of nuclei. A- mentioned above, the rods and c< >ne- 

 have not differentiated at this stage. At place-, e-pecially in the 

 MI of ihe retinal fold-, there are connect ive tissue cells which 

 fill in the spaces between these folds and the tape turn. 



The differentiation occurring in the lenticular region i- quite 

 strikin. . The tapetum continues anteriorly to a point 



0. Se 



Ret 



ens 



Cilp- 



T^- Hnt tp;tn. 



-Tap. 



H rieserv- ^ . - :'." ' ' 



I-n.. .}. Leu an.! 1.-:. >amc gi. ml .;. 



:lu-liiini II. M, i >:.. li < HluT 



: 



ju-t nie<liad \t> the margin "t" the leu- wlu-re it douMe- <m it-elf in 

 a pi^nieinle la\er <-l 'ell>. The <HM -errata, ciliar\' pr< - 

 and the iri> are pie-ent. The leu- it-elf i- >uppirtt-il l.y the 

 SUSpen-ury lii;anient . 



Ill it> differentiation, the len- i- (|iiile typical (Fig. 4). It i- 

 i'\-.il in shape, heiu^ coiup<>r-ed <>f a wide nucU-u- nf liln-r- with 

 their niedialK- located nuclei, and an anterior epithelial la> r. 

 Both are identical with the same part- of the normal of the >aine 

 age. The len- surface i- toward the ectodermal portion of the 

 chorio-allantoic membrane. The incorj)oration of the 



