GENERAL STRUCTURE OF THE CORNEA. 



373 



that have been dried or hardened in chromic acid, Mailer's 

 fluid, or alcohol, or which have been frozen. The layers vary 

 in thickness, the thickest layer being formed by the cornea 

 proper, which, in Man, is about one millimeter in thickness at 

 the outer border, whilst it is- somewhat thinner at the centre.* 

 The external epithelium stands next to this in thickness, being 

 in Man 0*03 of a millimeter thick.^ After this comes the 

 membrane of Descemet, with a thickness at its centre, in adults, 



Fig. 377. 



Fig. 377. Meridianal section through the cornea of an adult Man ; 

 the eye having been hardened in Mtiller's fluid. The section was 

 stained with carmine, and rendered transparent with oil of cloves. 



of 0-0060-008, and at its periphery of O'OI 0'012,i and 

 lastly, the endothelium of the membrane of Descemet. The 

 appearances presented in such sections by the external epithe- 

 lium, the membrane of Descemet, and the endothelium, require 



* Briicke, Anatomische Beschreibung des menschlichen Augapfefr, p. 9. 

 Berlin, 1847. 



t Henle, Handbuch der Eingeweidelehre, p. 605. Braunschweig, 1866. 

 J H. Muller, Archivfiir Ophthalmologie, Band ii., Abtheil. i., p. 48. 



