34 Journal of Comparative Neurology. 



two vesicles the anterior of which becomes the pineal eye. In 

 the third stage the anterior vesicle becomes constricted off to 

 form the pineal eye, while the posterior remains as the end of 

 the epiphysis. The development of the eye of Grammatophora 

 is somewhat similar to that of Lacerta described by Hoffmann, 



In the stages of Hinulia studied, the eye was already differ- 

 entiated from the epiphysis. Three stages were available. In 

 the first stage seven layers were found in the retina as follows: 

 (1) rods, occupying about one third of the whole thickness of 

 the retina ; (2) spherical nucleated bodies ; (3) spindle shaped 

 bodies, staining very deeply ; (4) cells similar to the second 

 layer; (5) spherical cells similar to the second and fourth layers; 

 (6) a clear region ; (7) a layer composed of round nuclei with 

 much connective tissue. In some places the retina seemed to 

 have a supporting network of connective tissue in which the dif- 

 ferent elements are imbedded. 



The optic vesicle was found to contain minute strands. 

 Ahlborn has described nervous strands in the optic vesicle which 

 Spencer as well as McKay suggested might be nothing more 

 than the coagulable remains of the fluid contents of the brain 

 cavity. The strands that can be seen in the optic vesicle of the 

 pineal eye of Hinulia and Grammatophora are identical with 

 the fine strands in the cavities of the brains of both lizards. In 

 the second stage pigment is deposited (1) in the lower ends of 

 the rods, (2) in the line of spherical elements, and (3) in the low- 

 est layer. Thus there is produced such an appearance, as de 

 Graaf has described in Anguis fragilis, of a row of rods super- 

 ior to the pigmented rods. The pigment is deposited in the 

 rods as minute particles in horizontal lines, while it seems to be 

 .in vertical lines in the body of the retina. In the third stage 

 the chief thing noticed is the further development of the pig- 

 ment, which now covers the whole of the rods in many places ; 

 and where the lens joins the retina, the pigment reaches through 

 nearly the entire thickness of the retina. It is also important 

 to notice that the pigment is developed in the lens. 



Throughout the three stages the eye is double-convex in 



