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TICKS OF THE BELGIAN CONGO AND THE DISEASES THEY CONVEY.* 

 By George H. F. Nuttall, M.D., Ph.D., Sc.D., F.R.S., 



Quick Professor of Biology in the University of Cambridge, in consultation with 



C. Warburton, M.A., F.Z.S. 



(With 48 Text- FIGURES.) 



Contents. 

 Introduction . . 

 Classification of ticks, together with a short illustrated account of species 



occurring in the Congo . . 

 General Biology of ticks 



Special Biology of Congo Ticks and their Relation to Disease 

 How to collect ticks and what to observe 

 How to raise ticks 

 Index to Congo ticks and their hosts 



PAGE. 



313 



314 

 339 

 342 

 348 

 349 

 351 



Introduction. 



The subject of ticks and the diseases they convey is one of great practical importance 

 to agriculturists and pathologists in such a country as the Congo. Of the species 

 recorded from the Congo, one conveys relapsing fever to man and eight have been 

 shown to convey diseases to domesticated animals in various parts of Africa. 



In the following pages a short resume is given of the classification of ticks. From 

 practical considerations of space and in the hope that this paper will prove useful 

 particularly to workers in the Congo, a technical and lengthy description of the 

 different species has been purposely omitted. Since we are only dealing with ticks 

 at present known to occur in the Congo — ^some 29 species — it will suffice if we give a 

 few of the main characters whereby these species can be distinguished. In this 

 connection we rely largely on illustrations which amplify the descriptions sufficiently 

 for the rapid determination of some of the commoner species. On the other hand, 

 it must always be remembered that to determine the species to which a tick belongs 

 is frequently a matter of considerable difficulty even to the expert. Some species 

 are easily recognised with the naked eye, others require careful examination under the 

 microscope. In the latter case they are best studied as opaque objects laid upon a 

 small cone of modelling wax which can be moved about so as to give the specimen 

 the desired orientation. A binocular microscope is almost essential, combined with 

 good illumination. 



* Written at the request of the Belgian Authorities. 

 (C221) Wt. P8/91. 1,000. 1.16. B.&F. Gp. 11/1. /l 



