On the presence of elastic fibres in the cornea / by J. Hamilton McIlroy.

  • McIlroy, J. Hamilton.
Date:
[1897]
Catalogue details

Licence: Public Domain Mark

Credit: On the presence of elastic fibres in the cornea / by J. Hamilton McIlroy. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    and celloidin produce the most picturesque sections, yet one misses much of the natural arrangement of parts, as this may be altered by such histological processes. For elastic fibres the method of partially macerating the cornea in dilute acetic acid for about three weeks, and making sections by freezing in a tan- gential direction, was the one that was most satisfactory. Mounting in glycerine was resorted to as a rule in the freezing method, as the treatment necessary to prepare for mounting in Canada balsam also causes shrinkage in the tissues. Fig. 1.—Human foetus of about six weeks. Vertical section of the cornea and lens. Low power. a, Corneal epithelium showing loosely scattered cells, b, Sub- stantia propria of cornea still homogeneous, but becoming invaded at margins, c, Epithelium of lens constriction com- plete, but lens lies close to cornea, d, Posterior segment of lens. The earliest period of foetal development of which material for examina- tion in the human foetus was obtained, was between five and six weeks. (Fig. 1 is from a photograph of vertical section through the front of this eye.) At this stage the cells arc still embryonic in character, and have not become differentiated into fibrous tissue, etc. Staining for elastin was entirely negative. The corneal epithelium is seen as a fairly narrow band which passes along in front of the cornea, the nuclei being scattered throughout its extent in a single layer. The lens with its epithelial covering is seen close to the corneal epithelium, but quite distinctly separated from it. The first appearance of the substantia propria of the'cornea, is seen in the narrow, homogeneous layer which separates the epithelium and the lens. VOL. XL. (THIRD SBR. VOL. I.)—APR. 1906 23