. Zoology. Zoology. 42 ZOOLOOT. eaten by the hog are developed in its body into the larval tape-worm (called in this species Cysticercus cellulosm, Fig. 42). The liead with its suckers is formed, and the body becomes flask-shaped; the Cysticerci then bury themselves in the liver or the flesh of I pork, and are transferred living in uncooked pork to the intestines of man. The body now elongates and new joints arise behind [ the head until the foim of the tape-worm is I attained, as in Fig. 41. The hinder joints then become filled with I eggs and break oil, becoming independent joints comparable
. Zoology. Zoology. 42 ZOOLOOT. eaten by the hog are developed in its body into the larval tape-worm (called in this species Cysticercus cellulosm, Fig. 42). The liead with its suckers is formed, and the body becomes flask-shaped; the Cysticerci then bury themselves in the liver or the flesh of I pork, and are transferred living in uncooked pork to the intestines of man. The body now elongates and new joints arise behind [ the head until the foim of the tape-worm is I attained, as in Fig. 41. The hinder joints then become filled with I eggs and break oil, becoming independent joints comparable with the "parent-nurses" of the Cercarias, except that they are not contained in the body of the Tjenia (as in »s««r-ti^g Cercaria), but are set free. The inde- cus, or larval ' Tape-worm, pendent joint is called a "; It escapes from the alimentary tract of its human host, and the eggs set free, in and about privies, are swallowed by that unclean animal, the pig, and the cycle of generations begins anew.*. Class II.—Nematelminthes {Round- or Tliread-worms). General Characters of Round-worms.—In these worms the body is round and tlircud-like, not being jointed. Many are parasitic: such are the Ascarids. The round-worm most dangerous to human life is the Trichina ftpiralis (Fig. 43). It is very minute, tlie female being 3mm. in length, and tlie male worm half as long. The female is capable of producing a thousand young. The eggs are eaten by rats, dead rats are sometimes devoured by pigs, and jiork thus infested when e.'iten by man, either raw or partly cooked, often causes the death of their hu- man host. The hair-worms (Gordiiis aquaticiis. Fig. 44) resemble a piece of a horse's hair, and are so-called because they are. 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 w
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1897
