602 MEDICAL ENTOMOLOGY 



sanguinens. Male. Length 2 mm.; width 1 to 1 '3 mm. Female. Length 

 7 mm. ; width 4 mm. This' variety is found in Zanzibar and Nubia. 



Rhipicephalns sanguinens is the invertebrate host of Piroplasma canis. 



Rhipicephalns appendiculatus, Neumann. Male, (Plate LXXVII, fig. 5.) 

 Scutum brown .; eyes flat and .elongated. Marginal festoons extending 

 to and bounding the extreme festoons, which are triangular in shape ; 

 a white margin surrounds the scutum. Numerous short punctations, 

 nearly all superficial, some anterior ones deep and arranged in rows. 

 Adanal plates triangular, at least twice as long as broad ; internal borders 

 longer than the external ;' posterior borders oblique and slightly concave. 

 Anus situated nearer the anterior ends of the adanal plates than the 

 posterior ; accessory plates well developed. Spiracles broad. Basis capituli 

 nearly as long as broad, with slight lateral projections near anterior third. 

 Coxa I with a conspicuous anterior hump or projection on the dorsal 

 surface. Caudal appendage well developed, twice as long as broad. 

 Length 4 mm. ; width 2'6 mm. (Neumann) 



Female. Scutum oval, longer than broad. Punctations numerous, 

 small and superficial. Basis capituli a little more than half the width of 

 the scutum. Porose areas small and circular, limited by longitudinal 

 ridges. Length 4 to 12 mm. ; breadth 2 to 7 mm. (Neumann) 



This tick is found in Cape Colony, German East Africa, British East 

 Africa and the Cameroons ; it is parasitic on cattle, goats, horses and the 

 dog. As already noted R. appendiculatus is the invertebrate host of 

 Theileria parva, the piroplasm which causes Rhodesian Cattle Fever or 

 East Coast Fever. 



R. appendiculatus may be mistaken for sanguinens ; it can be distin- 

 guished by noting the following points : The punctations on the male 

 scutum are much more regular than those of sanguinens ; the caudal 

 appendage is not so broad. It should, however, be remembered that the 

 caudal appendages of these ticks are as a rule only well developed 

 a few days after the males have fed. The appendage of appendiculatus is 

 usually a prominent structure and nearly always turns downwards. The 

 basis capituli in the female appendiculatus is broader than that of the female 

 sanguinens. Appendiculatus can nearly always be recognized by noting 

 that the first segment of the palp has a well -developed spur on its ventral 

 and inner border, and by the hump on coxa I. Donitz points out that 

 many of the specimens from German East Africa are not typical, the 

 punctations on the scutum being deeper and more thickly set, as in 

 R. bursa. 



Rhipicephalus simus, Koch, C. L. Male, (Plate LXXVII, figs. 3 and 4.) 



