328 
Ornithodorus moubata 
material was destroyed by a breakdown of an incubator at Oxford 1 in January 
1915, which prevented the confirmation or elucidation of many interesting 
features in the bionomics of this tick. 
SECTION I. BIOLOGY OF 0. MOUBATA. 
Nuttall and Warburton (1908) emphasise the fact that very little in¬ 
formation is available regarding the biology of this tick. The number of 
nymphal stages has not been established and it has been alleged that the 
imaginal stages may undergo ecdysis. The following observations were made 
therefore to determine the number of moults undergone by 0. moubata before 
and after reaching maturity, the changes taking place in the external anatomy 
of the ticks at each stage of development, and the duration of the different 
stages at different temperatures. At the same time records were kept of 
oviposition, copulation, longevity of the female and engorgement. 
Experimental Procedure. These observations were carried out on a series 2 
of isolated females kept at different temperatures. The adult ticks were kept 
in small glass-topped entomological boxes and their progeny in glass bottles 
of convenient size, plugged with cotton-wool. Small pieces of filter-paper, 
placed inside these containers, served to provide hiding places for the ticks 
and also to absorb the excrement. In the intervals between meals, these 
receptacles were maintained at constant temperatures in incubators. The 
ticks were fed upon a fowl, being placed in glass cylinders of small diameter, 
which could be held against the bare skin beneath the fowl’s wing. The 
individuals, hatched from each batch of eggs, were fed and reared as one 
group but, to avoid confusion of stages, the newly moulted ticks were separated 
daily from those which had not moulted. The lighter colour and softer texture 
of the integument easily distinguished the former from the latter. In some 
cases the ticks were weighed and measured both before and after feeding and 
the periods during which they remained attached to the fowl were recorded 
accurately. The parent ticks used in the following experiments were reared 
from nymphs received on 3. iii. 1913 from Livingstone, N. Rhodesia (Quick 
Lab. Cat. No. 2040), the stock material being therefore in a healthy condition. 
When a sufficient number of adult ticks had been reared from this stock, 
three series of six females were isolated and maintained at 22°, 30° and 37° C. 
respectively, together with their respective progeny. Newly emerged males 
1 After May 1914, the work was carried on, by permission of Prof. Bourne, in the Zoological 
Laboratory, Universit}^ of Oxford. 
2 Merriman kept records of five ticks only, reared at one temperature, from the first nymphal 
to adult stages. It was considered that results of greater value would be obtained by com¬ 
mencing with a series of females of known history and by rearing a portion of the progeny of 
each, at different temperatures. The work became very laborious, owing to the number of 
individuals involved and their feeding was, in consequence, somewhat irregular, as great care 
was necessary to avoid confusion of the different batches or individuals. 
The results of experiments conducted late in 1912 and early in 1913 were discarded, as the 
stock material at this date was derived from old females, which had undergone prolonged 
starvation, and was therefore of poor vitality. The immature stages raised from these females 
failed to pass beyond the third nymphal stage, probably because of this fact. 
