ANTERIOR LIMITING LAYER OF THE CORNEA. 399 



The resemblance of this layer to the mernbrana Descemetii 

 has already been referred to. It has also been regarded as the 

 analogue of the membrane of Descemet, and as such it has been 

 described by Bowman* under the term, lamina elastica an- 

 terior, and by Henlef as the external basement membrane. 



The existence of this layer cannot be denied, and it is owing to a 

 misapprehension that LanghansJ includes me with others who deny 

 its presence. 



I have however denied, and still continue to deny, that this layer 

 presents the same characters as the membrana Descemetii. The 

 above-mentioned terms therefore are not applicable to it. It may be 

 called by the name that Arnold || applied to it, of " sub epithelial layer 

 of the cornea," or " anterior limiting layer" (Reichert). 



This layer breaks up in the cornea of Man and of various 

 animals, after treatment with permanganate of potash, into the 

 same fibrils as the rest of the corneal tissue ; whilst the mem- 

 brana Descemetii, when subjected to the action of the same 

 solution, preserves its capability of rolling inwards, to which 

 we shall hereafter have to jefer, its splintery fracture and its 

 structureless aspect.^" The anterior limiting layer of the corneal 

 tissue is composed of extremely closely interwoven fibrils de- 

 cussating with each other at all angles. It is not of uniform 

 thickness throughout. It is strongly developed in Man, very 



* Loc. cit., p. 5. 



f Loc. cit., p. 605. 



t Loc. cit., p. 19. 



Loc. cit. , pp. 524 and 525. 



|| Die Bindehaut der Hornhaut und der Greisenbogen, (The connective 

 tissue of the cornea and the arcus senilis. ) Heidelberg, 1860. 



IT This layer forms the analogue of that which in the skin is termed the 

 corpus papillare, and has been treated of by Henle as the intermediate skin, 

 by Krause as the superficial layer of the corium, by Bowman as basement 

 membrane or tunica propria cutis, by Kolliker and Gerlach as the super- 

 ficial layer of the corium, by Virchow as the superficial layer of the 

 corium of the bed of the nail, and by Leydig as the homogeneous limiting 

 membrane of the corium, in regard to which my essay entitled Unter- 

 suchungen iiber die Struktur des Bindegewebes, (Researches on the structure 

 of the connective tissue,) Sitzuvigsberichte der Wiener Akademie, Band xxx., 

 p. 50, may be consulted. 



