JORDAN XIII 



PLATE 3 



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Transverse section ot a 3-dav embryo at level of tenth somite. The arrow points to 

 the cord of primordial germ-cells, extending from the sixth somite to caudal ex- 

 tremitv of primitive streak, at the lateral border of the area pellucida. Helly fix- 

 ation ; iron-hematox vlin stain. Photo, x 40 



Transverse section of a ^-dav ernbrvo at level near cephalic extremity of the entoder- 

 mal cords of primordial germ-cells. The two bilateral cords are more or less 

 interrupted or segmented. This section passes through an intersegmental region. 

 Certain germ-cells are also scattered more medially among the entodermal cells of 

 the area pellucida. Arrows point to germ-cells. Hellv fixation ; iron-hematoxvlin 

 ^tain. Photo, x 66 





