. Animal parasites and human disease. Insect Vectors; Parasites; Parasitic Diseases; Medical parasitology; Insects as carriers of disease. 244 THE TAPEWORMS rats and mice from the household and in keeping food out of their reach, and in guarding against the accidental ingestion of such possible intermediate hosts as fleas. A closely allied species, H. diminuta (Fig. 91), occurs rarely in man. It closely resembles the dwarf tapeworm but is of larger size #(four to 24 inches in length) and has no hooks on the scolex (Fig. 87H). The eggs develop in the larvae or adults of the mealworm, Asopia far


. Animal parasites and human disease. Insect Vectors; Parasites; Parasitic Diseases; Medical parasitology; Insects as carriers of disease. 244 THE TAPEWORMS rats and mice from the household and in keeping food out of their reach, and in guarding against the accidental ingestion of such possible intermediate hosts as fleas. A closely allied species, H. diminuta (Fig. 91), occurs rarely in man. It closely resembles the dwarf tapeworm but is of larger size #(four to 24 inches in length) and has no hooks on the scolex (Fig. 87H). The eggs develop in the larvae or adults of the mealworm, Asopia farinalis, and in adult beetles, forming cysticercoids. When these are eaten by rats, mice or man they transform into adults. In an experiment' on man the eggs of the adult worm were found in the faeces 15 days after the eating of an infected mealworm. The larvae of a number of species of fleas also become infected when they ingest the eggs. It is evident that prevention consists in guarding carefully against the accidental swallowing of mealworms with cereals or other foods, and in cautioning children against putting beetles or other insects into their mouths. Although the worm is rare in man it is common in rats and mice in many parts of the world, and occurs in nearly all parts of the United States. Other Tapeworms (Taeniidae). — A con- siderable number of other tapeworms of this family have been found in man, acciden- ce tally occurring in him, or having a very limited distribution. Fig. 92. Davainea mad- Q£ thoge with limited distribution should agascariensis; A, head and . neck, B, gravid progiottids. be mentioned two species ol Davainea. One, xs (A, after Bianchard, D madaqascariensis (Fig. 92), is a small B, after Daniels.) v , - i tapeworm reaching a length ol ten or twelve inches. It is found, chiefly in children, in many tropical countries, especially in islands and seaports and on ships. The suggestion has been offered that the intermediate host, so far unknown, may


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Keywords: ., bookcentury1900, bookdecade1910, booksubjectparasites, bookyear19