ON HABITS AND PECULIARITIES Of SOME SouTH AFRicAN Ticks. 291 
investigated in other countries. B. decoloratus is by far the most common 
of all the South African ticks, but it is unable to thrive on the dry 
plateaux and where the rainfall is scanty. The ox is its chief host, but it 
freely attacks the horse, ass, sheep, and goat, and has been fed to maturity 
on the dog. In the southern districts of Cape Colony another Boophilus 
is found in abundance on cattle. This species appears to differ in no 
character from the Boophilus found on cattle in Queensland. Neither do 
we find any essential difference between it and B. microplus of South 
America. We shall here refer to it as B. australis Fuller, by which name 
it is known in our records. Both &. decoloratus and B. australis very 
closely resemble the type species, B. annulatus, not only in structural 
characters, but also in habits and in the duration of the various life stages. 
The adult-larva stage occupied twenty-one to twenty-six days in our 
incubator; at ordinary temperature of the laboratory the extremes 
recorded are 40 and 146 days for B. decoloratus and 35 and 149 days 
for B. australis. The stay of the female on the host, from the time 
it attaches as a larva to the time it leavés as an adult, is generally 
twenty-three days ; in our numerous records it has varied from eighteen to 
thirty-eight days. Part of this period is spent in feeding, and part in under- 
going the transformations from larva to nymph and from nymph to adult. 
The nymph and adult attach to the host close to the moulted skin of the 
previous stage. If the fed larva or fed nymph is removed and kept at 
the temperature of the air, it takes much longer to moult than if on the host. 
The male, after feeding a few days, releases its hold and roams about for a 
mate. He generally remains on the host about a month after reaching 
maturity. Two to three generations of these species are probably passed 
in one year. 
The third South African Boophilus does not appear to have been 
described. It is much larger than the other species and of distinctive 
appearance. The horse is its favourite host amongst domestic animals, 
and when running on the veld it may become very heavily infested during 
the winter months in many districts of Cape Colony. The ox is said 
to be little troubled by the species, even where the horse is very much 
troubled. Few specimens have been found during the summer months. 
Most complaints of injury come from high inland districts, but the true 
explanation of this fact may be that greater numbers of horses are raised 
there than in other parts—not that the climatic conditions are more 
favourable for the species than at the coast. The adult-larva stage in our 
laboratory has taken 18€ to 201 days; on the veld it probably takes even 
longer. Attempts to force development in the incubator have failed, all 
of the numerous females of this species that have been exposed having 
soon perished. Very little success has attended attempts to feed larvee in 
the summer, and hence it is suspected that the species normally passes 
through one generation only in the year. 
In closing this paper I wish to mention that there are doubtless many 
more species of ticks to be collected at the Cape than are here discussed. 
It is even probable that I have overlooked some species occurring com- 
monly on cattle. Doubtless, too, many features of interest in the life- 
cycles and host habits of even the species best known yet remain to be 
disclosed. 
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