a1 The Hebrew University of Jerusalem
Differences between sexes in the duration of larval and nymphal quiescence in Ixodid ticks were investigated in Israel in the laboratory. In H. dromedarii Koch the larval quiescence of the male was, on average about 4 hours longer than that of the female, but in Rhipicephalus sanguineus (Latr.) no significant difference was found. In five species a statistically significant difference in the length of nymphal quiescence was found between males and females; in three of them, R. sanguineus, R. secundus Fel.-Muh. and H. dromedarii, that of the male exceeded that of the female by 1/2 to 1 1/2 days and in the other two, H. marginatum Koch and H. excavatum Koch, the opposite was found, the difference being 1·3 and 3·7 days, respectively.
(Received August 19 1965)
* This investigation was partly supported by Research Grant AI01006 from the National Institutes of Health. U.S. Public Health Service.
† Department of Parasitology.
‡ Department of Statistics.