852 Genus Haemaphiisalis 



what may bo considered a normal coxal armature to which a large 

 number of species of Haemaphysalis conform in both sexes (Fig. 860). 

 It consists of a moderate internal spur on coxa I (which is sub- 

 triangular), a slight spur at the middle of the posterior borders of coxae 

 II and III, and at the internal angle of coxa IV. If a $ specimen 

 possesses anything more pronounced than this in the way of coxal 

 armature it is pretty certain that the cT coxae will be unusually 

 spinose. 



All species of Haemaphysalis have a blade-like dorsal retrograde 

 spur on trochanter I. Some species have ventral retrograde spurs on all 

 or some of the trochanters, and these are excellent specific characters 

 usually to be found both in the <^ and in the $ . Many forms have a 

 hardly perceptible prominence in that position, but we shall only 

 speak of the trochanters as " spurred " if this characteristic is readily 

 recognizable. 



Species belonging to the genus Haemaphysalis are less readily 

 identified than Ixodes by means of a dichotomic key, because, as 

 already stated, there are few salient features which serve to 

 differentiate them. The diagnosis has frequently to be based on 

 numerous minor points which, in the aggregate, permit of the identifi- 

 cation of a species, due regard being paid to individual differences 

 which may be fairh? marked. Stress must be laid for this reason upon 

 accurate figures to accompany the text. 



Although Neumann (1901, p. 340) designated H. concinna Koch 

 as the type of the genus, the cT of this species is atypical in that its 

 palps are unlike those of any other member of the genus. Of the 

 four species originally included by Koch, who founded the genus 

 Haemaphysalis, only a second species, H. cinnabarina, remains which 

 would take priority over H. concinna and might, with better right, be 

 designated as the type of the genus. 



We have attempted a linear arrangement of the species, beginning 

 with atypical forms like H. inermis, with the palps simple and non- 

 salient laterally, and proceeding by degrees to species like H. dentipalpis 

 with complex, strongly salient palps. No such arrangement can be 

 more than partially successful, but it is hoped that nearly allied species 

 will in most cases be found in tolerably close juxtaposition. 



