320 Transactions of the lioyal Society of South Africa. 
time when the parasites of East Coast Fever were very frequent in the 
blood. 
Gleaning the Ticks. — The larvae moulted in due time, and the nymphge 
were placed on Cow 596 on April 7, 1910. Cow 596 developed the 
disease after an incubation time of 15 days, and was killed for experi- 
mental purposes on the 12th day of the East Coast Fever illness. 
Bemarks. — The nymphge collected as engorged larvae off Heifer 923 
whilst undergoing an East Coast Fever reaction proved to be infective for 
Cow 596. 
Note. — The nymphte which communicated the disease to Cow 596 
engorged and were collected off this cow from April 13 to 15, 1910. 
They moulted into adults on May 20, 1910, and were used for the infesta- 
tion of cattle Nos. 1022 and 1060 {vide Experiment No. 1 C," Nos. 21 
and 22). 
{h) Khipicephalus appendiculatus, imagines (Eef. No. 309). 
Note. — The engorged females originated from Natal on December 9, 
1909. The eggs were laid on December 24, 1909, and the larvae hatched 
out on January 30, 1910. 
Infectmg the Ticks. — The larvee were fed on Calf 700 from February 
27, 1910, and dropped between March 2nd and 7th, that is, from the 7th 
and 8th days of the disease, and at a time when Theileria parva were 
frequently met with in the blood. 
Cleaning the Ticks. — The engorged larvae moulted on March 17, 1910, 
and the nymphge were placed on Calf 917 on March 30, 1910. This calf 
developed East Coast Fever after the usual period and died ; the examina- 
tion of the blood proved the presence of Theileria parva, and the glands 
contained Agamonts and Gamonts in large numbers. 
Bemarks. — The ticks which as larvae were fed on Calf 700 during the 
time of the East Coast Fever reaction proved virulent for Calf 917 in their 
nymphal stage. 
Note. — The nymphae which communicated the disease to Calf 917 
engorged and were collected from April 3 to 7, 1910, namely, a week 
after infestation. They moulted into adults on May 4, 1910, and were 
placed on Heifer 1088 on December 15, 1910, and on Calf 1145 on 
January 6, 1911, in order to test their infectivity {vide later Experiment 
No. 1 "C," Nos. 23 and 24). 
(c) Ehipicephalus appendiculatus, imagines (Eef. No. 335). 
Infecting the Ticks. — The larvae which originated from females col- 
lected in Natal on December 19, 1909 ; the eggs were laid on December 
24, 1909, and the larvae hatched out on January 30, 1910. On February 
