Volume 1

A system of human anatomy : including its medical and surgical relations / by Harrison Allen. With a section on histology. By E.O. Shakespeare.

  • Allen, Harrison, 1841-1897.
Date:
1882-1884
Catalogue details

Licence: Public Domain Mark

Credit: A system of human anatomy : including its medical and surgical relations / by Harrison Allen. With a section on histology. By E.O. Shakespeare. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    oOO^ and sometimes processes of considerable length, and more or less branched, spring from them. A single cell will generally spread across two or more bundles. When this is the case, the indentation of the space caused by the convex surface of two bundles coming together, is tilled out by the substance of the cell- plate. In consequence of this circumstance, when the cell-plate is detached from its position and examined at once, a ridge extends from one parallel side of the cell to the other (see e, B, fig. 2, Plate III.). This ridge appears like a band running in the body of the cell when the latter is viewed in surface. Sometimes it may be developed into a secondary cell-plate of some width, springing from the first, thus complicating the form of the cell. These cells are known as the flat tendon-cells of Ranvier. They may very justly be re- garded as a special form of endothelium. The cell- plate is elastic, and contains an ovoid nucleus near one straight side. It consists of an intercellular network which corresponds with the extent of the elastic plate. and at the notched sides extends beyond the plate into the processes; and the nucleus contains an inter- nuclear reticulum. Seen edgewise, these flat tendon- cells appear spindle-form, and when seen in optical or real transverse section they present a more or less branched or stellate aspect. Stellate cells.—-In loose connective tissue, or areolar tissue, where the bundles of fibrils intercross in every conceivable direction, the most irregularly formed minute lymph-spaces are found. These spaces are more or less stellate, and they often contain one or more fixed stellate cells. These are the connective- tissue corpuscles^! P^^ excellence. They lie in the small lymph-cavity, loosely attached to one of the sides of the space. The simplest form of this cell in adult tissue is that of a thin cell-plate of more or less irregu- lar outline, and containing an ovoid nucleus. The nucleus has an enveloping membrane of double con- tour, and contains an intra-nuclear, very dense net- work, the nucleus seeming to be implanted nearer to EXPLANATION OF PLATE I. Eig. \. Peritoneal surface of tlie centrum tendineiim of a Rabbit, silver-stained and highly inagiiitied. (After Klein.) h. Smaller endothelial plates, situated over the straight lymphatic vessels which lie between («) the tendon-bundles; e, true stomata, some widely open, some collapsed,—they form a means of conmiunication between the serous cavity of the peritoneum and those straight lymphatics last men- tioned, and are lined with endothelial cells of a germinating character; the dotted line starting from c represents the outline of a lymph-sinus below the surface, and in communi- cation with the before-mentioned straight lymph-vessels. Fig. 2. Highly magnified view of the spine-covered ej)i- thelial cells of the rete mucosum, or deep layer of the cutaneous epithelium. The section is parallel with the surface, and includes some underlying connective-tis- sue. (After Ranvier.) a. Bloodvessels with surrounding lymph-spaces; f, con- nective-tissue bundles cut transversely; b, union of the epi- thelium with the tissue of the cutis; e, polyhedral epithelial cells of the rete mucosum, containing oval nuclei and minute brilliant nucleoli. These cells are united together by means of their spines, c ; an intercellular cement fills the interspaces ibrraed by the spines. Fig. 3. Various forms of epithelium, fresh and much mag- nified. (After Ranvier.) a, Thin, broad, epithelial scale I'rom the inside of the cheek, showing a very small nucleus, and finely-gi'auular contents,—the imjirint of adjoining cells is observable in the innermost line; b, smaller cpithelia, from the deeper epithelial layei's of the bladder, and c, a larger epithelial cell from a more superficial layer; d, an isolated spinous epithelial cell from the rete mucosum of the skin ; n, the nucleus of a ciliated columnar epithelial cell, whose vibratile cilia are shown at g; h, the elastic striated plate from which project the cilia of a smaller ciliated columnar epitiielium; ]}, q, the deep extremities of columnar cells. Fig. 4. Tiiree isolated columnar epithelia from the intestine. h, The striated elastic plate which limits their free ex- tremity ; n, the oval, double-contoured nucleus of the cell. Fig. 5. A. Profile view of epithelia of the bronchus of a Rabbit, showing, between the regular ciliated columnar epi- thelium, d, the existence of branched cells, e, of a different nature, whose processes form a more or less complete network with each other, as well as a communication with the branched connective-tissue corpuscles, a. B. A surface view of the same epithelia, the letters hav- ing a similar indication. C. Shows a longitudinal section of a minute bronchus. d, Columnar epithelia, of which, c are the cilia ; v is the muscular coat, the smooth muscle-fibres being cut trans- versely; a is a lymph-vessel of the adventitious coat of the bronchus. (Alter Klein.)