4T0 
BI()1o<jji of Txodulae 
It is worthy of note that this tick has been much less prevalent on 
stock in South Africa of recent years in consequence of the cattle there 
being subject to systematic dipping operations. Thus, the representa¬ 
tive of Messrs Win. Cooper and Nephews, writing to me from East 
London in October, 1912, states that their farm is practically free from 
A. Jiehraeum, adding “where we used to lose 90 % of our calves from 
Heartwater we now lose none, that is to say our losses in the last two 
years from this cause have been one calf ” ; they rear about 150 animals 
a year upon the farm. Similar reports have reached me from other 
cjuarters, and I had difficulty in obtaining living ticks in 1912 for these 
raising experiments. 
The only author who has studied the biology of A. hebraeinn is 
C. P. Lounsbury. The observations recorded in his papers (Lounsbury 
(1) 1899, 16 pp.; (2) 1900, pp. 21 et seq .; (3) 1900 a, pp. 41-44 ; (4) 1902, 
pp. 47, 66-69; (5) 1904, pp. 15-20^^) have been fully confirmed. His 
records are very brief, so that it is possible to incorporate them wholly^ 
in brackets in the following pages. Lounsbury outlined the main 
features of the life-history of the species and deserves great credit 
especially for having demonstrated that A. hehraeum conveys the disease 
Heartwater to cattle, sheep and goats. 
The time A. hebraeum remains wpon the host. 
Larvae 
Host main¬ 
tained at 
N umber of gorged 
Date when 
average 
larvae collected on 
Lot 
Host 
put on host 
temp, of 
successive days 
Remarks 
N. 1732 
Ram 
14. I. liJ13 
4° C. 
0 on 
day 
5 
[Lounsbury 
100 
0 
(1) states that 
292 
7 
the larvae stay 
453 
. 5 
8 
4-9, but gener¬ 
312 
,, 
9 
ally 0-7 days 
183 
10 
on the host.] 
90 
11 
50 
J? 
12 
24 
J J 
13 
12 
14 
0 
J J 
15 
1 
99 
10 
2 
99 
17 
1 
99 
18 
1544 
1 See our Bibliography of the Lrodoidea. Cambridge, 1911; Lounshiiry’s paper.s are 
referred to by the numbers (1-5) respectively in these notes. 
“ The part played in pathology is excluded. 
