32 
J. R. AUDY 
of trombiculid mites are shown as (a) the total number recorded, with the number of these 
which were “new”, i.e., undescribed at the time of collection (a number which of course must be 
taken with caution), (b) the number of these species in each of four generic groups, related 
respectively to Trombicula (filiform sensillae), Schongastia (clubbed sensillae ; including 
Walchiella ), Gahrliepia (the genus sensu lato after Womersley), and the Leeuwenhoekiids 
(including Hannemania). 
The names listed under the head of Responsible Investigators have as far as possible been 
restricted to those who were actually responsible for the investigation of the trombiculid mites, 
and not those colleagues who were responsible for the study of the animal hosts or the other 
parasites. The names have been placed in alphabetical order except where one of a pair of 
workers has borne particular responsibility for the investigation. Extracts of this table, 
compiled from published accounts, have been sent to many of the workers concerned for 
checking, and the writer is indebted to H. S. Fuller, C. E. M. Gunther, G. M. Kohls, R. N. 
McCulloch, C. B. Philip, R. V. Southcott, R. Traub, and H. Womersley for their help. In the 
case of the collections made by the China-Burma HQ of the U.S. Typhus Commission, and 
the extensive collections made by NAMRU 2, it was impossible to prepare a summary from 
published accounts. The writer is therefore particularly grateful to Traub for providing all 
the data for the former collection and to Wharton for all the data from the registers of NAMRU 
2. Unfortunately no replies were received up to the time of going to press from the All-India 
Institute for Public Health in Calcutta so that their considerable collections in Bengal are here 
represented (entry 28) by the data given provisionally by Krishnan et al. (1949). The T. muris 
of that paper is here treated as Euschongastia indica. The author directly responsible for the 
work with mites is not known to the present writer but he believes it was Dr. R. O. A. Smith. 
The writer has been in contact with Mr. M. G. Raja Varma, Research Fellow of the Indian 
Council of Medical Research, who has been working under Dr. Smith at the Bengal Typhus 
Enquiry. Entry No. 28 A relates to work done between 1950-1952, the data being derived from 
correspondence with Mr. Raja Varma who has very kindly allowed the summary to be included 
in the Table. 
The responsible organisation has been shown wherever the investigation concerned was 
part of its avowed policy. In spite of all efforts to be accurate, there will be discrepancies in 
and omissions from this table, to which the writer would appreciate having his attention drawn. 
Except for the lumped entry (55) for Sasa and others, no mention is here made of the 
extensive collections recently made in Japan and Korea in connexion with studies of epidemic 
haemorrhagic fever (EHF). 
Acknowledgement should be made to a number of collectors whose names do not appear 
in the tabular summary. Apologies are offered to those whose names are inadvertently omitted 
from the list of these contributors : S. L. Allman, R. H. Baker, T. O. Berge, J. M. Bonin, 
A. A. Bullock, R. C. Bushland, R. K. Carter, H. M. Cooper, W. D. Exton, W. D. Fitzwater, 
W. K. Ford, J. M. Fritts, C. J. Hackett, J. Hake, D. E. Howell, Major Hicks, D. Johnson, 
J. R. Kinghorn, G. H. McQueen, J. R. Mangram, I. M. Mackerras, M. J. Mackerras, F. J. 
Mitchell, A. Mundan, L. A. Posekany, K. N. A. Rao, T. M. Rivers, M. L. Roonwal, J. N. 
Strong, D. C. Swan, A. Rau, G. M. Rio. The following permanent institutions have sponsored 
a considerable amount of work on chiggers : South Australian Museum, Adelaide (Womersley), 
the Laboratory of Pathology and Microbiology at Cairns (D. J. W. Smith and formerly, E. H. 
Derrick) and at Brisbane (Heaslip), the Queensland Institute of Medical Research, Brisbane ; 
the Institute for Medical Research, Kuala Lumpur ; Kitasato Institute for Infectious Diseases, 
Tokyo ; All-India Institute of Hygiene and Public Health, Calcutta ; U.S. Army Medical 
Service Graduate School, Washington. 
STUD. INST. MED. RES. 
