39 



PLATE IV. 



Fig. 13. Cross-section of vitreous body of 23 mm embryo, 

 showing the many fibrous outgrowths of the hyaloid arterial system 

 and of the numerous free mesoderm cells, also the union of these 

 mesodermal elements with the vitreous body. Magnification 350 

 diameters. 



Pig. 14. Section of eye of 100 mm embryo. Blood vessels form 

 two distinct systems, one surrounding the lens, and the other lying 

 close to the retina. Numerous fibers of blood vessels. Note espe- 

 cially fibers running parallel to retina. Magnification 95 diameters. 



