Independent Development of the Lens. Al] 
Dererpty BurtieED Eyres witHoutr LENSES 
Fia. 26. A section of a thirteen day embryo which was treated with alcohol. 
One eye faces outward and contains a lens, while the other faces in toward the 
median plane of the head and is without a lens, probably never having come in 
contact with ectoderm. 
Fic. 27 A section of a nineteen day embryo more posterior in the same series 
than section, fig. 6. The deeply buried defective eye has no lens. 
Fig. 28 Section of thirteen day embryo after treatment with alcohol. Sec- 
tion passes in front of the median plane of the right eye which is well differentiated 
and contains a lens. The other eye is small and scarcely differentiated, buried in 
the tissue below the brain and contains no lens. A normal ear exists on the side 
with the large eye and a small defective ear is on the other side in more posterior 
sections. 
