176 The Elastic Tissue of the Iluinan Larynx 



the slow method of celloidin infiltration, as recently recommended by 

 Miller.' ■ 



Sections, fifteen micra in thickness, were made and mounted serially. 

 The sections were passed through a mixture of alcohol and glycerine, 

 from which they were transferred to a paper corresponding in size to 

 the cover-glass to be used. The paper Avas then inverted upon a slide, 

 which had previously been coated with a thin layer of albumin fixative. 

 Between two slides thus prepared a piece of filter paper was inserted, and 

 the two slides were tied together. They were then placed in a thermostat 

 until dry, when they were removed and placed in equal parts of absolute 

 alcohol and ether to remove the celloidin. The sections are always firmly 

 attached, and no care need be exercised to prevent their floating oif. This 

 method Avas devised by Prof. E. C. Jeffrey. Weigert's resorcin-fuchsin 

 method was used to stain the elastic fibers. Orange G. as a counter- 

 stain offers a sharp contrast to the blue-black of these fibers. Van 

 Gieson's picro-fuchsin was used in studying the collagenic fibers and the 

 nodules found in the anterior extremities of the vocal cords. 



Henle ' describes beneath the mucous membrane of the larynx an elastic 

 fiber layer, which in some regions is poorly, and in others well developed, 

 and in some closely and in others loosely connected with the epithelium. 

 Where this layer is thickened after removal of the mucous membrane or 

 the tissue which covers them externally, there remain ligaments. These 

 ligaments are attached at definite points to the perichondrium of the 

 laryngeal cartilages, and such points of attachment may be regarded as 

 the points of origin of the ligaments. It is not to be disregarded, how- 

 ever, that the elastic fibers of these ligaments are in direct continuity 

 with the elastic elements of the whole mucous tract, and that, therefore, 

 their limits are not sharp and are arbitrarily made. 



Following the classical description of Luschka * the elastic tissue of 

 the larynx may be divided for descriptive purposes into three zones, 

 corresponding to the three compartments of this organ. The inferior 

 zone includes all the elastic tissue within and below the ligamenta vocalia ; 

 the middle zone includes the elastic tissue surrounding the ventriculus 

 laryngis; the superior zone includes the elastic tissue of the membrana 

 quadrangularis and epiglottis. The discussion of the arrangement of 

 the elastic fibers will be proceeded with in the order given above. 



= Miller: J. of Applied Microscopy and Laboratory Methods. Rochester, 

 N. Y., Vol. 6, No. 4. 



^ Henle: Handb. der Eingeweidelehre des Menschen. Braunschweig, 1873, 

 p. 254. 



■•Luschka: Der Kehlkopf des Menschen. Tiibingen, 1874. 



