62 



EVOLUTION OF THE HUMAN EYE 



in man and apes from that met with in other mammals. 

 In the human eye the fibers of which it is composed radiate 

 out in a fan-like fashion from the position where Descemet 's 

 membrane ends, and the angle of the anterior chamber is 

 prolonged outward 0.8 mm. beyond that point. So that 

 if a line vertical to the surface of the eye be drawn back- 



Fig. 15. — Ciliary body of the Rhesus monkey. 



ward through the canal of Schlemm it passes into the angle 

 of the anterior chamber (Fig. 17). If the same line be 

 continued backward it almost passes through the large 

 circular artery at the base of the iris, and only a small portion 

 of the ciliary processes lie to its inner side. In the lower 

 mammals the ligamentum pectinatum is a much more 



