588 BRAIN AND NERVES. 



by the altered ratio of diffusion. A cloudiness of the lens may also be 

 produced in life by a rapid removal of water, as, for example, when a 

 frog is plunged into a salt or sugar solution. The appearance of cloudi- 

 ness in diabetes has been attributed by some to the removal of water. 

 Opinions on this subject are, however, conflicting. 



The average results of four analyses made by LAPTSCHINSKY 1 of the 

 lens of oxen are here given, calculated in parts per 1000: 



Proteins 349.3 



Lecithin 2.3 



Cholesterin 2.2 



Fat 2.9 



Soluble salts 



Insoluble salts 2.4 



In cataract the amount of proteins is diminished and the amount of 

 cholesterin increased. This statement requires further substantiation. 2 



The quantity of the different proteins in the fresh moist lens of oxen 

 is as follows, according to MORNER 3 : 



Albumoid (lens fibres) 170 p. m. 



/3-Crystallin 110 " 



a-Crystallin 68 " 



Albumin. .. 2 



The corneal tissue has been previously considered (page 525). The 

 sclerotic has not been closely investigated, and the choroid coat is chiefly 

 of interest because of the coloring-matter (melanin) it contains (see 

 Chapter XVI). 



TEARS consist of a water-clear, alkaline fluid of a salty taste. Accord- 

 ing to the analyses of LERCH 4 they contain 982 p. m. water, 18 p. m. solids 

 with 5 p. m. albumin and 13 p. m. NaCl. 



THE FLUIDS OF THE INNER EAR. 



The perilymph and endolymph are alkaline fluids, which, besides salts, 

 contain in the same amounts as in transudates traces of protein, and in 

 certain animals (codfish) also mucin. The quantity of mucin is greater 

 in the perilymph than in the endolymph. 



Otoliths contain 745-795 p. m. inorganic substance, which consists 

 chiefly of crystallized calcium carbonate. The organic substance is very 

 similar to mucin. 



1 Pfliiger's Arch., 13. 



2 See Gross, Arch. f. Augenheilk., 55 and 58. 



3 I.e. 



4 Cited from v. Gorup-Besanez, Lehrbuch d. physiol. Chem., 4, Aufl., 401. 



