. Sanitary entomology; the entomology of disease, hygiene and sanitation. around the toenails. Many 366 SANITARY ENTOMOLOGY animals, including man, hogs, dogs, cats and the larger domestic animals,are attacked. The flea {Xenopsylla scopulifer Rothschild) occurs on rats in Ger-man East Africa. It is closely allied to A, cheopis and partially replacesthat species in the region mentioned. Its possible relations with plaguetransmission have not been determined. FACTORS INFLUENCING ABUNDANCE OF FLEAS There is a very close correlation between various climatic factors andflea abundance. This applies
. Sanitary entomology; the entomology of disease, hygiene and sanitation. around the toenails. Many 366 SANITARY ENTOMOLOGY animals, including man, hogs, dogs, cats and the larger domestic animals,are attacked. The flea {Xenopsylla scopulifer Rothschild) occurs on rats in Ger-man East Africa. It is closely allied to A, cheopis and partially replacesthat species in the region mentioned. Its possible relations with plaguetransmission have not been determined. FACTORS INFLUENCING ABUNDANCE OF FLEAS There is a very close correlation between various climatic factors andflea abundance. This applies to practically all species in greater orless degree. In the United States it may be said that in general fleas. Fig. 70.—Head of rooster infested with the sticktight flea {Echidnophaga gallinacea).Somewhat reduced. (Bishopp.) From U. S. Dept. Agr., Bull. 248, fig. 7. are more abundant during moderately warm weather when there arefrequent rains or high humidity. The effect of seasonal and climaticconditions on fleas has a very important bearing on the plague. Thishas been well shown by the Indian Plague Commission which found thatthere is a rather close correlation between the abundance of fleas and theprevalence of the disease, and that flea abundance in turn depended uponclimatic conditions. They showed that in the case of the European ratflea there is a marked decrease in numbers with the oncoming of the hot,dry season. These fleas begin to disappear in early April and from May15 to November not a single specimen is seen. The Indian rat flea,which is the principal plague conveyer in that region, was found to beabove the mean average in number during the period from November toMay, with the
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectbenefic, bookyear1921
