. Animal parasites and human disease. Insects as carriers of disease; Medical parasitology. species of crabs in Formosa, and Yoshida, another Japanese in- vestigator, acting on the discovery of his countryman, found the larvae in a fourth species of crab in Japan. The crabs most com- monly infected are Potamon obtusipes, a coarse-shelled, chestnut- colored crab about one and a half inches in diameter, and P. dehaanii, a slightl}^ smaller ,.^™_,_,^-,«5gs^a^ species, grayish black or red- crabs bound in the shallow waters of mountain streams, and the former species is sometimes used as food. An-
. Animal parasites and human disease. Insects as carriers of disease; Medical parasitology. species of crabs in Formosa, and Yoshida, another Japanese in- vestigator, acting on the discovery of his countryman, found the larvae in a fourth species of crab in Japan. The crabs most com- monly infected are Potamon obtusipes, a coarse-shelled, chestnut- colored crab about one and a half inches in diameter, and P. dehaanii, a slightl}^ smaller ,.^™_,_,^-,«5gs^a^ species, grayish black or red- crabs bound in the shallow waters of mountain streams, and the former species is sometimes used as food. An- FiG. 72. A common fresh-water crab Other implicated SpCcicS, of Japan, Eriocheir japordcus, which serves EviOcheiv UlVOflicUS fFiff 72) as a host for lung fluke. (After Yoshida.) . ' , . ,, , . IS abundant m all plams rivers in Japan and is a common article of diet throughout the country. It is a larger crab, reaching a diameter of three inches, and has large hairy claws. The fourth species, Sesarma dehaani, is of medium size, dark in color with light reddish claws, and inedible. Miyairi has shown that in Korea another crab, Astacus japonicus, is the intermediate host. The lung fluke cercariffi encysted in these cral>s (Fig. 73A) were found chiefly in the liver while young, but when older they -OS. - '. Fio. A, encysted ccrcaria of human lung fluke, Paragonimus ringeri, from gill of crab; B, larva emerging from cyst. o. s., oral .sucker; int., intestine; ex. v., excretory vesicle; v. s., ventral sucker. X 50. (.\fter ) occur in the gills. They vary in number from a few to several hundred. In .some localities a very high per cent of crabs are infected, Nakagawa reporting that practically 100 per cent are infected in one district in where the lung fluke is very common. The cysts containing the cercariae are nearly round, mm. (5*5 of an inch) or less in diameter, and have relatively. Please note that these images are extracted from scanned
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectmedical, bookyear1918
