occxir in the adanal shields, which are rounded posteriorly and 

 laterally; the accessories tend to be obsolete, and subanal 

 shields fail to develop (See Hyalommina , pages 520 to 522 J. 

 Large females are typical of the species but small females 

 have smooth cervical grooves, narrow tail of spiracular plate, 

 and unhanded legs. 



H. asiaticum asiaticun and H. asiaticum caucasicum (both 

 considered as synonyms of H. dromedarii by Delpy - HH^ are here 

 considered as separate geographical rsices with distinct morpho- 

 logical characteristics. Under experimental conditions they 

 mate readily and produce fertile progeny. Male H. a. asiaticum 

 vary from 2.5 mm. to 7.0 ram. in length and from T.2~mm. to 4.0 mm. 

 in width. Their critical characters are minute punctations com- 

 bined with large punctations (both sparse); wide white parma; 

 strongly concave basis capituli; and very narrow tail of spira- 

 cular plate. In every lot of H. a. asiaticum , one encounters 

 specimens grading from this suBspecies to H. a. caucasicum , 

 males of which measure from 2.5 mm. to 6.0~mra. in length and 

 from 1.2 mm. to U-O mm. in width and average 0.5 mm. smaller 

 than those of H. a. asiaticum. Scutal punctations of the two 

 subspecies are'^similar, on small males of both only minute 

 punctations may be present. The fusion of festoons of H. _a. 

 caucasicum is variable; however, the tail of the spiracular 

 plate is wide and the tarsal pads are large, these characters 

 vary but little. Females of H. a. caucasicum differ from fe- 

 males of H. a. asiaticum not only by smaller size but chiefly 

 by larger tarsal pads and absence of rings on legs; the width 

 of the tail of the spiracular plate may be either like that 

 of H. a. asiaticum or wider. 



Parthenogenetic females of H. dromedarii give rise to many 

 deformed larvae, those that survive are all females not outwardly 

 distinguishable from normal specimens. Both sexes are represented 

 when F]_ females are mated with males. 



NOTE. Yugoslavia. In various lists of Yugoslaviai ticks pre- 

 sented by Oswald (see Bibliography) H. dromedarii or syno- 

 nyms of this species are not included. The possibility 

 that material mentioned in the following two papers refer 

 to a different species in this genus must be considered. 

 Specimens have been requested from Yugoslavian workers. 



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