of the Crystalline Lens after Death. 197 



had examined, were positive, the next structure negative, and the 

 external one jiositive. 



In the lens of another horse, whose age was also unknown to 

 me, the remains of three structures were visible ; but the two 

 positive ones, namely, the central and external structures, had 

 just disappeared, but were not encroached upon by the interme- 

 diate negative one. They were therefore black when seen by 

 polarized light, as shown in fig. 7, while the remaining negative 

 one was of the most brilliant yellow colour. 



In the lenses of a third horse, probably of an intermediate 

 age, I found a structure intermediate between that of the two 

 preceding ones. The following were the dimensions of its 

 lenses : — 



The first lens having been carefully prepared and immersed in 

 distilled water, exhibited the beautiful optical figure which is but 

 imperfectly represented in fig. 8. The central sectors were posi- 

 tive, but faintly illuminated. The wide and brilliant yellow 

 and white structure was negative, and the external structure, 

 which had just begun to appear, was positive. 



On the second day the black mass round the central sectors 

 had enlarged itself, and become very black, having the form of a 

 square lozenge. The yellow ring has risen in its tint to a bril- 

 liant pink yellow at the edges, the white ring within it having 

 increased in width, and the white ring without it having di- 

 minished. 



On the third day the diameter of the lens had increased to 

 0-86 in all directions, and its thickness from 0-50 to 0*717 of 

 an inch. The coloured ring has not changed greatly. 



On the fourth day the bright pink of the negative structure 

 has risen to a bright blue, the pink and yellow being seen at its 

 margin ; and the external positive structure seems to be now 

 conjoined with the blue negative structure, in consequence, no 

 doubt, of the extension of the latter to the margin of the lens. 

 The thickness of the lens was now upwards of 0-86, and the 

 capsule came off, in consequence of which two of the blue sec- 

 tors have become of a pale pink colour. The instant the capsule 

 came off, the lens shrunk in all its dimensions nearly the tenth 

 of an inch. 



The second lens on the third day gave exactly the optical figure 

 shown in fig. 8, having been newly placed in distilled water ; 

 but the external ring seems to be slightly negative, like the yel- 

 low one. Its appearance was grayish and indistinct. 



