FIBRILLAR STRUCTURE OF THE CORNEA. 395 



depends on the fact that the fibrils resist destruction longer 

 than the rest of the substance of the cornea, i.e. the inter- 

 fibrillar part of the matrix and the cells. 



Portions of corneal tissue treated with permanganate of 

 potash do not give any so called Xantho-proteinic acid reaction,* 

 which is not the case with the fresh cornea; this becomes 

 thoroughly yellow on boiling with nitric acid and the addition 

 of ammonium chloride. 



Moreover the fibres are rendered easily isolable by macerat- 

 ing sections of the fresh cornea in a ten per cent, solution of 

 common salt,f myosin dissolving out into the solution, from 

 which it can be again obtained by the addition of powdered 

 salt or of water. 



Bruns:}: first extracted myosin from the cornea, and attributed its 

 origin to the corneal corpuscles. He therefore believed he had sup- 

 plied chemical evidence of the contractility of the corneal corpuscles 

 demonstrated by Kuhne. Schweigger-Seidel, however, owing to his 

 views respecting the corneal cells, is altogether opposed to the idea 

 that the myosin proceeds from them. Kuhne || states that watery 

 extracts of the cornea contain a large quantity of paraglobulin, which 

 probably proceeds from the corpuscles. A. Schmidt^f produced coa- 

 gulation in transudates by the addition of fragments of fresh corner. 

 Funke** has demonstrated the presence of albuminate of soda, albu- 

 men, and casein, in the watery extract of the cornea. Brunsff also 

 obtained an albuminate of an alkali from the watery extract of the 

 cornea, and refers the origin of this albuminous body to the fluids 

 permeating the matrix. From what has now been said it is obvious 

 that a knowledge of the distribution of the albuminous substances in 

 the cornea belongs to the category of much wanted but vainly hoped 

 for desiderata. Moreover, it has not been proved that with the 



Rollett, loc. cit., pp. 523 and 524. 

 f Schweigger-Seidel, loc. cit, pp. 308 and 352. 



* Medicinisch chemische Untersuchungen. Herausgegeben von F. Hoppe- 

 Seyler, Heft ii., p. 260. Berlin, 1867. 

 Loc. cit., p. 352. 



1 1 Lehrbuch der physiologischen Chemie, p. 386. 

 IF Reichert and Dubois' Archiv, p. 675, 1861. 

 ** Lehrbuch der Physiologic, 2nd Edition, 1858, Band ii., p. 160 

 ft Loc. cit. 



