segments thicker in the middle forming a sharp angle 
externally. First segment has not five or seven 
bristles on its ventral inner chitinous plate as Eurhipi- 
cephalus has ; (5) Coxa I only slightly incised, with 
two stumpy processes. S very small, about two 
millimetres. Scutum very convex, punctate, four 
rows of hairs. Two pairs of anal plates having their 
sides parallel, not triangular. External plate as long 
as internal. 
2 . Very small scutum, posteriorly it is V-shaped, 
not polygonal as in Eurhipicephalus. 
Bionomics .—Ticks of this genus remain on their 
host all their life, from the larval stage till they drop 
off to lay eggs. From egg to adult stage lasts about 
three weeks and the whole life is about nine weeks. 
Neumann considers that there is only one species, 
viz., M. annulatus (— bovis ), and that australis 
decoloratus , caudatus , etc., are merely varieties. Donitz 
considers that there are at least two species. 
(1) M. decoloratus .—The blue tick. S. The 
four anal plates all end in a sharp point, often projecting 
beyond the hind margin. First segment of palpi on 
the lower and inner side has a stumpy appendage 
bearing a single bristle. Tail present. Radula (hypo- 
stome), six rows of teeth. Rhodesia, Cape Colony. 
Pathogenicity .—Transmits P . bigeminum. 
(2) M. annulatus (= Boophilus bovis and M. 
australis ).—The common blue tick. Tail absent. 
Radula, eight rows of teeth. Japanese varieties have ten 
rows of teeth. Anal plates have stumpy ends. 
Pathogenicity .—Transmits P. bigeminum. 
Genus Haemaphysalis 
Base of rostrum rectangular, twice as broad as 
long. Eyes absent. Anal shields absent in $ . Second 
