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ENTOMOLOGY FOR MEDICAL OFFICERS 



/ Body oval, distinctly narrowed anteriorly A. reflexus. 



I Body elliptical, blunt and hardly narrowed anteriorly = 6. 



Body twice as long as broad ; basis capituli narrowed posteriorly 



= A. cucumerinus (Peru). 

 Body hardly longer than broad, basis capituli rectangular and well 

 in front of coxae of first pair of legs 



= A. transgariepinus (South Africa). 



"Dorsal integument with large polygonal depressions ; tarsi with 



well-marked dorsal terminal protuberance, giving an appearance 



7. ^ of a bifid tip = A. brumptii (on man in Somaliland). 



Dorsal integument almost smooth ; tarsi not appearing bifid 



= A. aqualis (German East Africa). 



Argas persicus (Oken) ; the Fowl-tick (Fig. 123). The 

 body is flat, oval, and narrowed anteriorly ; general integu- 



Fio. 123. — jlr^os ^'ersicus. 



ment finely wrinkled, almost granulous, with numerous 

 platelets ; margins formed of quadrangular areolae ; basis 

 capituli broader than long. Found on birds, but particularly 

 on fowls, ducks, geese, and turkeys, in all parts of the world ; 

 in Persia it is said to attack man commonly. It lives in 

 cracks of walls, particularly of poultry-houses. It is fatal to 

 fowls by spreading among them the specific spirillum of 

 chicken cholera ; but when it attacks a fowl in force the 

 envenomed bites and the loss of blood alone are sufficient 

 to cause death. In Persia its bite is feared by natives, and 

 is said to be actually dangerous to foreigners. 



According to observations collected and confirmed by 

 Nuttall, the eggs are laid in batches in the cracks where the 

 ticks hide, and begin to hatch in about three weeks. The 

 larva, which has three pairs of legs and an anterior capitulum, 



