FEEDING TIMES 
183 
Summary 
1 . In order to estimate actual populations of trombiculid mites, or to compare populations 
of different species on the basis of infestation data, we must have estimates of the mean feeding 
times of the larvae (chiggers). 
2. Feeding times were estimated by keeping infested rats and mice in small cages over 
trays of water and counting the chiggers which had detached daily. 
3. Chiggers from three sources were timed: laboratory bred chiggers fed on white mice; 
those found on marked rats which had been trapped within two days of release : and those on 
trapped wild rats of unknown origin. 
4. The interpretation of results from chiggers of the first two groups is straightforward. 
Chiggers of the third group, however, have been on the rat for an unknown period before 
trapping. Two methods of estimation from the observed data are tried and give reasonably 
consistent results. 
5. Estimates of the mean, modal, and maximum feeding times are given for 21 species, 
and casual records for 15 more. 
References 
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MALAYA, No. 26 . 1953 
