XXV TICKS 



311 



in length and 6 mm. in breadth. It resembles the 

 common bed-bug and lives in huts, retiring into cracks 

 in walls or Hoors or in the grass-covered roof during the 

 day and becomes active at night ; then, if the 

 opportunity offers, it attacks man and l:)east. 



Tliis species is common along lines of travel and 

 usually abounds in rest-houses ; it is apt to get into 

 bedding or sleeping mats which remain for the night in 

 rest-houses. Old camping-grounds should always be 

 avoided. 



Ticks suffer from the uncertainty of finding a suitable 

 host, but this is counterbalanced by tlieir extraordinary 

 powers of fasting, for they can remain several months 

 without food. 



In recent years ticks have acquired some importance ; 

 it has been proved by a series of most careful and 

 brilliant researches that these parasites are capable of 

 conveying a serious disease to cattle and to man. In 

 order to appreciate the manner in which these diseases 

 are inoculated into animals, it is necessary to be familiar 

 with the main features in the life-history of ticks set 

 forth in the preceding paragraphs. 



It is an important feature in tick disease that young 

 ticks hatched in the laboratory can communicate the 

 disease. This means that the parasite can pass from 

 the mother-tick to the egg. This fact was discovered 

 by Smith and Kilborne in their investigation of Red- 

 water, or Texas fever of cattle. 



Tick fever is defined as a specific disease caused 

 by the j)resence in the blood of a minute parasite 

 or hsematozoon, known as a spirochfeta, which is intro- 

 duced by the bite of a tick known as Ornithodoros 

 moubata. The disease can also be conveyed by in- 

 fected blood. 



Tick fever was described by Dr. Livingstone, from 

 observations made in the basin of the Zambesi, but it 

 has been met with in the Congo Free State, Central 

 Africa, German East Africa, and in Uganda. It was 



