334 
Transactions of the Boyal Society of South Africa. 
That is to say, 12 days, 25 days, and one month after they had 
moulted. 
Rhipicephalus appendiculatus, nymphae (Ref. No. 864). 
These ticks failed to transmit the disease in seven instances out of ten, 
the three positive cases being Cattle Nos. 1043, 1017, and 1050. These 
ticks hatched on April 26, 1910 (the same as batch No. 363, belonging to 
the same original lot), and were placed on Heifer 908 on August 12th, 
namely, about 107 days after they had hatched. They moulted into 
nymphae on September 10, 1910. 
They were placed on the following animals : — 
627 on September 
15, 1910, and 20 
911 
20 
1068 
20 
1050 (died) „ 
7 
1082 
20 
1014 
20 
1046 on October 20, 
1910 8 
1043 (died) 
6 
1090 
6 
1017 (died) 
10 
Of the animals infested on September 15th one died, and of the 
animals on October 20th two died. It is remarkable that in this instance 
the minimum number of ticks (6 and 10) transmitted the disease. 
Rhipicephalus appendiculatus, nymphge (Ref. Nos. 355 and 356). 
These ticks failed to transmit the disease in four instances when used 
together for the purposes of infestation. 
The larvae of batch 355 hatched on iVpril 26, 1910, and when they were 
79 days old were infected with East Coast Fever ; they moulted into 
nymphae on September 1, 1910. 
Larval ticks number 356 hatched on April 18, 1910, and when 95 days 
old were infected with East Coast Fever ; they moulted into nymphae on 
August 15, 1910. 
They were placed on the following cattle : — 
627 on September 30, 1910, and 14 became attached 
911 20 
1014 „ „ 10 
1068 „ 14 
