526 EMBRYOLOGY OF THE LOWER VERTEBRATES CH. 



completely fused. Posteriorly the neural folds seein to be continuous 

 with the lips of the primitive groove. A faint continuation forwards 

 of the primitive groove may he seen in the floor of the rhomboidal 

 sinus. 



pa 



or 



ms. 



. ' 



//JN 



Fi'.. 'l'-\\. UlastmiiTiii uitli Fowl embryo with al>out 10 or 11 inesodcrni M-L;inriit>. 



t : I,, lii-ail : |fc/ in.-.liillary f'olil ; ?H.S. iii.->mliTiii s.-iiiMit : 

 ;it i<- rniliiiu-iit : pa, prDaniiiinn. 



Iiiijtoriani incsodci in t'ciitun-s an- in le noticed. The nmttled 

 appearance of the vascular area pm.lii.-r.l h\ tin- i iidiin.'nis <.!' hlno.l- 

 veisels developing in lh<- -planHmir iiifs..lcnn is conspicuous. The 

 formerly isolated vascular rudiments (white in the li^-uiv an- now 

 becoming joi in -i i up i., i',,nn a net \\ork ami tlu- net work can be traced 

 'Hid and ui a .- ma 1 l-r >ca If aOIOBa Mn 1 pellucid area. At 



