. A manual of zoology. Zoology. Fig. 26.^.—, end, and ventral views of head and hinder end of male Ascaris iuuibiifoides. (From Hatschek.) inhabits the small intestine, often in enormous numbers. The females average about .5-6 inches, the males 4 inches, in length. The ani- mals are enormously prolific, a female containing about 60,000,000 eggs. The eggs (fig. 246, a) are easily recognized. Shortly after fertilization the eggs pass out of the intestine with the faeces, but develop without intermediate host if in the course of two or three months, when the embryo has developed, they are
. A manual of zoology. Zoology. Fig. 26.^.—, end, and ventral views of head and hinder end of male Ascaris iuuibiifoides. (From Hatschek.) inhabits the small intestine, often in enormous numbers. The females average about .5-6 inches, the males 4 inches, in length. The ani- mals are enormously prolific, a female containing about 60,000,000 eggs. The eggs (fig. 246, a) are easily recognized. Shortly after fertilization the eggs pass out of the intestine with the faeces, but develop without intermediate host if in the course of two or three months, when the embryo has developed, they are taken into the human intestine. The development of the pinworm, Oxyuris vermicularis,* is somewhat similar except that the embryos are developed in the egg at the time of oviposition, and hence after a shorter stay outside the body are capable of infection. The white worm, not half an inch long, lives in the rectum, especially of children, and in crawling outside the anus causes intolerable itching. Ascaris mystax* occurs in dogs and cats (occasionally in man). A. megalo- cejjhala * (a favorite animal for cytological researches) and Oxyuris equi in the horse. These do little harm. On the other hand Heterakis maculosa often destroys whole flocks of pigeons. Family 3. Strongylid^. These are readily recognized by the bursa of the male, a broadening of the hinder end of the body by two ring-like. Fig 'Wi —Anterior end of Ankylnstomum duodennle. dorsal and side views. ", inner, )>, iiiiter ventral teeth : c, dorsal tooth of m, mouth capsule ; d, stylet; e, ventral ridge ; oe, cescjphagus. processes, which contains two spicula. Frequent but not constant is a widened capsule surrounded by papillae at the mouth. A number of species of Strongylus occur in domestic animals. Syngamus trachea-. 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 perf
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectzoology, bookyear1902
