. Agricultural zoology. Zoology. 234 ZOOLOGY. of a suitable host, the joint and the egg-shells, or the latter only, as the case may be, are digested in the stomach or intestine, so that the larvse are set free. These (Fig. 137) are spherical, glass-like, of micro- scopic size, as might be expected, and bear three pairs. Fig. 136.—The Common Tapeworm (TfEwia officindlis) : a, head and neck, strongly magnified; J}, joints, natural size; c, eggs, strongly magnified. of booklets, by means of which they quickly perforate the wall of the gut, and make a way through the tissues of the host. They may
. Agricultural zoology. Zoology. 234 ZOOLOGY. of a suitable host, the joint and the egg-shells, or the latter only, as the case may be, are digested in the stomach or intestine, so that the larvse are set free. These (Fig. 137) are spherical, glass-like, of micro- scopic size, as might be expected, and bear three pairs. Fig. 136.—The Common Tapeworm (TfEwia officindlis) : a, head and neck, strongly magnified; J}, joints, natural size; c, eggs, strongly magnified. of booklets, by means of which they quickly perforate the wall of the gut, and make a way through the tissues of the host. They may also be carried further by the blood-stream. The larva of a particular species settles down finally, not only in some particular kind of host, but also in some defi- nite organ or tissue. It then loses its hooks, and is rapidly trans- formed into a hollow bladder-worm, (measle), which grows till it reaches a definite size, depending on the species. Meanwhile it gradually develops one (Crjsticercus) or several (Gcenurus) in- FiG. 137. — Tapeworm Larva (of TiEnia solium), mucli Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Bos, Jan Ritzema, 1850-1928; Ainsworth Davis, J. R. (James Richard), 1861-1934. London, Chapman & Hall, Ld.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1894
