CHILOPODA 



217 



headache, and backache if the poisons enter a vein. Locally, an 

 ulcer may form at the site of the bite. 0. talaje Guerin Meneville 

 causes severe itching and pain. 



With regard to the Ixodidae, Ixodes ricinus causes severe der- 

 matitis, which may be followed by pustules and abscesses, with 

 oedema, lymphangitis, and lymphadenitis, associated with fever. 



Treatment— The treatment of tick-bites is first to detach the 

 tick, which is by no means easy, as the recurved teeth of the 

 hypostome hold on to the wound very firmly. The best plan is 

 to rub any oil into the ventral surface of the tick, thus interfering 

 with its respiration, and compelling it to detach itself from the host. 

 With regard to 0. turicata, it is advised to apply the actual cautery, 

 as the effects of the bite are so severe. According to Wellman, 

 Ornithodoros bites should be treated by bathing in very hot water, 

 after which bicarbonate of soda should be applied in strong solution. 

 Itching may be allayed by a menthol ointment (i to 2 per cent.). 



Fig. 20. — Scolopendra movsitans Linnaeus. 



As regards prophylaxis, badly infected native huts should be 

 burnt, while ordinary houses may be fumigated with sulphur or 

 carbon bisulphide, or sprayed with kerosene or boiling water. 

 Beds must always be raised from the ground, and the feet of the 

 bedstead placed in water containing kerosene, while pyrethrum 

 powder may be dusted between the coverings of the bed. Wellman 

 insists that natives should not be allowed to sleep in or near the 

 quarters of Europeans. 



2. Chilopoda. 



The class Chilopoda includes the Scolopendridse, or centipedes, 

 which are animals with a head and a uniformly segmented trunk, 

 possessing numerous legs. They are very common all over the 

 world, but the tropical species are much larger than those which 

 inhabit the Temperate Zone. They live under stones in shady 



