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ture of the vitreous body as deduced from entoptical phenomena. He 

 is now of opinion that the arborescent system of which he infers the 

 existence in that part of the eye (Proceedings, p. 209) does not con- 

 sist of tubes filled with globules or cells, as he at first supposed, but 

 of cell-constituted filaments. In a note, dated March 27, 1855, he 

 gives the following enunciation of his present views as to the struc- 

 ture of the vitreous body : 



" In the vitreous humour are innumerable transparent globules, 

 beads or cells, of less specific gravity than the fluid, extremely 

 minute, and of uniform size, which are arranged, without exception, 

 in rows to form the threads of a lax, elongated, irregular web, 

 springing from the general surface of the capsule by, commonly, 

 exquisitely small meshes, and extending into the interior by others 

 of increasing size, so that the innermost part of the web which lies 

 nearer the circumference of the vitreous body than its centre con- 

 sists of comparatively large ones. 



" Whenever the eye rotates, this filamentous peripheral system 

 will in its relative (counter) rotation, gradually, though soon, come to 

 the end of its tether, and in this interval and when there, act as a 

 check upon the relatively rotating fluid ; perpetually reiterating ob- 

 struction, above all in the immediate vicinity of the capsule and (by 

 the disposition of the threads to float vertically) most effectually in 

 the most important or horizontal direction. The middle of the 

 vitreous body being free of impediment, relative rotation of the fluid 

 expends itself there, whilst a practical concurrence in the ocular ro- 

 tation ensues near the capsule. And thus in the incessant move- 

 ments of the eye, head and body, the wall that confines the fluid can 

 suffer no severe concussions from eddies in the latter. In other 

 words, we have herein a provision that the crystalline lens may not 

 be shaken, the circulation in the retinal vessels may not be deranged, 

 and sensations of light may not be ever assailing us from impulses 

 of the vitreous fluid, perhaps that the retina may not itself suffer 

 direct injury therefrom," 



