On the anatomy of a new species of pentastoma found in the lung and air-sac of an Egyptian cobra / by George Harley.

  • Harley, George, 1829-1896.
Date:
[1857]
Catalogue details

Licence: Public Domain Mark

Credit: On the anatomy of a new species of pentastoma found in the lung and air-sac of an Egyptian cobra / by George Harley. Source: Wellcome Collection.

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

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    crease ia size and distance from each other. They then continue of the same relative size and distance apart ('2 Hnes) till within about half an inch of the posterior extremity, when they again, however, become smaller and more closely approximated. In all the four specimens which I examined, the rings were twenty-seven in number, and where largest, projected nearly half a line from the surface of the body. In the fresh specimen, when examined with a pocket lens, the ex- terior of the rings appeared mottled with faint white-coloured spots. Thev were and still are quite opaque, whereas the intervening tissue is so thin and transparent, that the internal viscera can be seen through it. A number of white bands or cords appear to connect one ring with another ; the bands are largest in the lateral and dorsal regions. A dark-coloured line extends along the back throughout the whole length of the body : this, as I shall afterwards have occasion to show, is the digestive canal. On the vmder surface, in the centre and near to the anterior margin of the head, which is slightly flattened from before backwards, is a round foramen, the mouth. On either side of this opening are two depressions, equidistant from each other, each containing a prehen- sile booklet of a bright yellow colour. These booklets in shape closely resemble a cat's claw, which can be extended and retracted at pleasure, and when completely drawn in, the points of them can be neither seen nor felt. The obtuse posterior extremity has a deep cleft across it, and on its under surface are two openings, one in front of the other: the anterior is the entrance to the vagina, the posterior the anal aperture. Anatomy of the Entozoon. Parietes.—The whole body is invested with a delicate, smooth, transparent cuticle, which can be readily detached by slight mace- ration. Beneath the cuticle are two layers of striated muscular fibres (PI. XLVII. fig. 13), a vertical and a transverse layer;—the longitudinal fibres are by far the most developed ;—the circular are in some places entirely wanting. The projecting rings, on the other hand, are not composed of striated muscular fibres, but consist of fibro-areolar tissue. They seem to serve as fixed points of action for the longitudinal muscles ; appearing to supply, in fact, the place of a hard skeleton. The interior of the abdominal cavity is lined by a fine transparent membrane, on which I thought I could detect a single layer of delicate pavement epithelium. Digestive Systejn.~T\\e alimentary canal, in consequence of its peculiar dark saffron tint, is readily traceable from its commence- ment to Its termination. It begins at the mouth, and runs in an almost perfectly straight line to the opposite extremity of the body, terminating, as was before mentioned, immediately behind the orifice ot the vagina (PI. XLVI. fig. 4, a). Close to its commencement It IS ot the diameter of a fine crow-quill, and may be said to continue 01 nearly the same size throughout its whole course. It lies directly