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Transactions of the Boyal Society of South Africa. 
EXPERIMENT No. 1 {continued). 
"C." TO SHOW THAT THE TICKS WHICH AS NYMPHS HAD COMMUNI- 
CATED THE DISEASE TO SUSCEPTIBLE CATTLE (Nos. 596, 561, 908, 
919, 914, 1012, 1026, and 1040), OR WHICH HAD PASSED THEIR 
NYMPHAL STAGE ON ANIMALS ARTIFICIALLY IMMUNISED 
Nos. 829, 883, 836, 895, 1047, 1033, 871, 621, 895, 836, 679, and 615) 
DO NOT TRANSMIT THE DISEASE IN THEIR ADULT STAGE TO 
SUSCEPTIBLE CATTLE. 
(/) Rhipicephalus appendiculatus (Eef. No. 268). 
^o^e.— The following Cattle Nos. 1022, 1060, 1088, 1045, 1057, and 
1058 were all born and bred in areas free from East Coast Fever, and 
accordingly were susceptible to the disease. 
21. Heifer 1022 was infested on June 23, 1910, with brown adults off 
Heifer 928 (Kef. No. 268). This infestation was repeated on June 28th, 
July 15th, July 20th, July 28th, August 3rd, and August 20th. Altogether 
100 ticks were placed on this heifer, but not all of them became attached. 
Remarks. — This animal remained quite healthy. 
22. Heifer 1060 was infested on August 29, 1910, with brown adults 
of Heifer 923 (Kef. No. 268), and was re-infested on September 14, 1910 ; 
8 ticks of the first infestation were counted to be fast and 18 of the 
second lot. 
Bemarks. — This heifer remained healthy. Later she was used for 
inoculation purposes, and was finally exposed to East Coast Fever 
infection on the farm " Burnside," Natal, and died on the 21st day of 
East Coast Fever {vide article on " Progress Eeport on the Possibility 
of Vaccinating Cattle against East Coast Fever," Experiment 6 D "). 
23. Heifer 1088 was infested on December 15, 1910, with a large 
number of brown adults which as nymphae had given the disease to 
Cattle Nos. 561, 908, 919, 914, 917, 1011, 1012, 1026, 1040, or which 
as nymphs had fed on immune Cattle Nos. 1047, 1033, 871, 621, 895, 
836, 679, 615, 829, and 883 ; the ticks were fast on December 16, 1910. 
Bemarks. — Heifer 1088 did not contract East Coast Fever from this 
infestation, but was used later for inoculation purposes (vide article cited 
above, Experiment 9 " J ") ; finally was exposed at " Burnside " and died 
of East Coast Fever complicated with Eedwater. 
24. Calf 1145 was infested on January 6, 1911, with large numbers of 
brown adults off Cattle Nos. 561, 908, 909, 914, 917, 1011, 1012, 1026, 
1040, 1047, 1033, 871, 621, 895, 836, 679, 615, 883, and 829. 
Bemarks. — The calf did not contract East Coast Fever from this 
infestation, but died from Enteritis on February 14, 1911. 
