Annals of the Transvaal Museum. 
85 
coxae contiguous, decreasing in size from the first to the fourth pair,, 
striated on the ventral surface, granular on the dorsal and posterior 
surfaces, with a transverse granular pad at the distal extremity ; the 
second article wider than long in the first two pairs of legs, longer 
than wide in the other two pairs; dentate on distal edge, with a 
distal granular pad ; third article wider at the distal extremity ; fourth 
article short in the first three pairs of legs, twice as long in the 
fourth pair ; fifth article provided on its dorsal border, in the first 
three pairs, with three successive teeth, the two proximal quadrangular,, 
the distal conical ; on the fourth pair only two conical teeth ; tarsi 
provided on their dorsal border with three teeth, one basal (on the' 
proximal pseudo-article of the last three pairs of legs), the second 
close to the first (both quadrangular), the third conical near the distal 
extremity ; swollen or blunt hairs fairly numerous, and a few spines 
on all the articles except the coxae. 
Hosts.- — Man, goats, sheep, and other mammals. 
Habitat. — Somaliland, Kilimanjaro, Congo, Egypt, South-East 
Africa, India. It is also said to occur in German South-West 
Africa. It is usually found in loose soil in the shade of trees 
and rocks in desert tracts, places chosen by animals for rest. 
There has been considerable confusion between this tick, its variety 
caecus, and 0. moubata. I have seen only specimens of 0. savignyi 
caecus, but after a careful study of the published descriptions and 
illustrations of the other two, I have come to the conclusion that if 
moubata can he considered as separate from savignyi, it must be only 
as a variety of the latter species. The main difference between these 
two seems to be that moubata lacks the eye spots, which are present 
in savignyi, and that the inner apophysis of the mandibles are 
bidentate , while in savignyi they are U7ii-dentate . Moubata cannot 
be considered as identical with savignyi caecus, although both forms 
lack eyes, because caecus agrees with savignyi in having the inner 
apophysis of the mandibles uni-dentate . The form of the last two* 
articles of the legs of these three forms, which is a character considered 
in other species, seems to differ in no essential detail. 
A study of the life history of moubata and caecus shows that they 
agree in all but one point. Dutton and Todd (.1905) state that the* 
larva of moubata sheds the egg-shell and moults to the nymplial 
octopod stage at the same time. Such is not the case with caecus. 
The larva hatches as a true larva with six legs. It crawls about for 
a short time, but does not feed ; then it becomes motionless, the outer- 
skin dries, and, after a time, the octopod nymph emerges. 
Taking all these points into consideration, it seems that we must 
consider these three forms as distinct, but the differences do not seem 
to me to be of importance enough to consider them as distinct species. 
My opinion is that both caecus and moubata are merely varieties of 
savignyi, and should be known as 0. savignyi caecus and 0. savignyi 
moubata. 
