62 FFRNANDUS PAYNE. 



divided into two distinct lobes, the anterior being much smaller 

 than the posterior. The gland completely surrounds the eye 

 except over the anterior face. Its secretion is poured into the 

 conjunctival sac and from thence into, the mouth cavity. The 

 large size of the gland in Typlilops led Duvernoy to the conclu- 

 sion that its function was not connected with the eye. As its 

 secretion, in Ainpliisbcena, is poured into the conjunctival sac and 

 thence into the mouth cavity, its function must have been, pri- 

 marily at least, connected with the eye. 



No eye muscles are present in Amphisb&na. 



The eye is directed outward and forward and makes an angle 

 of about 60 with a line drawn tangent to the dermal plate which 

 covers it. 



Whether the eye is still used as a sense organ, I cannot say, 

 but since the parts are so well developed and the eye is not 

 buried very deeply beneath the surface, I am inclined to believe 

 that it is at least, susceptible to light. 



The Sclera.- -The sclera (scl., Fig. 6) has apparently under- 

 gone no degeneration whatever. It compares favorably with that 

 of Anolis. In fact, there is but little difference in its structure in 

 the two eyes. At the proximal part of the eye, the sclera mea- 

 sures 1 2 // in thickness, while at the same place in Anolis it mea- 

 sures i 5 it. It is continuous over the front of the lens as the 

 cornea, which together with the thin wall of the conjunctival sac 

 at this place measures 7 //. Scleral cartilages extend from about 

 the middle of the eye back almost to the optic nerve. On each 

 side of the sclera and forming a part of it, are thin irregular layers 

 of pigment in patches. 



T/ic Choroid. - - If the blood vessels in the choroid still persist, 

 the preparations do not show them. All that can be seen is a 

 number of densely pigmented cells, around -and between which 

 are filaments of connective tissue (c/ir., Fig. 6). At the entrance 

 of the optic nerve, this layer measures 8 it in thickness, but 

 gradually becomes less forward and vanishes entirely a short dis- 

 tance back of the enlarged end of the pigment layer. The pecten, 

 present in Anolis, is not apparent in Amphisbcena. 



Tlic Lens. - -The lens has retained its natural shape and posi- 

 tion (lens, Fig. 6). It is almost spherical and measures So//, in 



