Schiilze (1921) recognized this grovrth phenomenon for mate- 

 rial of "H. rhipicephaloides " from a "steinbock" (probably meaning 

 an ibex) near tne Dead Sea in Palestine, although he continued to 

 apply a species name to these nints. Yet, Schulze and Kratz have 

 presumed to refer to this as a "half-endoparasitic type of para- 

 sitism" by ticks. Large number of ticks were foixnd in pale red- 

 dish cysts in the ibex's subcutaneous tissue, especially in the 

 axillae. Holes in the host skin could not be detected. 



In several instances we have found cast larval skins en- 

 casing subdermal nymphs. Young jirds raised to adulthood in 

 the laboratory yielded dead H. excavatum in the middle of the 

 stnmner when the hosts were sacrificed, and nymphal skins were 

 found around them. We have no evidence that a Hyalomma tick 

 overgrown by the host's skin can force its way out .through the 

 skin. 



Pavlovsky, Pervomaisky, and Chagin (1954), in preliminary 

 studies, have also indicated that when H. excavatum (= H. anato - 

 licum) feeds in large numbers on a restricted area of tEe host, 

 poorly developed specimens result. Females especially do not 

 fully engorge and may even die due to inflammation of the host 

 skin. When other species also compete for a restricted area of 

 the host skin, an additional antagonistic factor increases the 

 chances of abnormal development or death. 



Prolonged infestation on rabbits by H. excavatum under lab- 

 oratory conditions does not confer host immunity, preventing en- 

 gorgement by subsequent larvae, against this species or against 

 Dermac enter picttts (Chabaud 1950A, Brumpt and ChabatJd 1947). 



REMARKS 



A capillary tube arrangement, which has proved successful 

 for the artificial feeding of adults of H. excavatvim for physio- 

 logical and disease- transmission studies, has been described by 

 Chabaud (1950A) . 



Schulze (1932c) illustrated the leg segments (of "H. anato - 

 licum?*) to support theories of tick ornamentation. In The same 



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