S. Hadwbn and G. H. F. Nuttall 
299 
Date Day 
8. VII. 13 1 A single D. vaiustus ? was placed upon the dog. 
Temperature ”F. 
a.m, p.m. 
2 
100-6 
The tick. attcached itself on the right side of 
the neck, just in front of a line Joining the 
scapular angles 
3 
101-6 
101-4 
4 
102 
101 
5 
101-4 
100-2 
6 
99-4 
100 
7 
100-8 
101 
8 
101 
101-2 
9 
101-2 
101-2 
Symptoms of paralysis appeared, hind quarters 
affected; dog very restless and falling about 
when attempting to walk. Front legs fairly 
under control. Sensation in hind legs un¬ 
impaired but movements incoordinate. 
10 
100 
101 
Front limbs affected; dog could only raise his 
head a little, incontinence of urine. Loss of 
appetite. 
11 
12 
100 
101 
101 -i 
99-8 1 
Dog looking very ill, breathing laboured, had 
to be fed, paralysis persisting. 
13 
99-2 
99 - 2 J 
14 
99-2 
99-6 
Symptoms subsiding. 
15 
100-6 
— 
Almost well. 
16 
— 
—■ 
Dog as well as ever, can run and jump over 
obstacles. 
18 
Tick removed. 
about 1 gorged. 
This experiment demonstrates conclusively that a single tick is capable 
of producing “Tick Paralysis” in the dog. 
Negative results luith a Horse and Jackal. 
On 25. vir. 1913, two H. venustus $s, which were all that survived 
of the ticks collected 5. vi. 1913, by Mr Stanford, were placed upon a 
jackal and a horse respectively after the ticks had been placed overnight 
at 30° C. Both ticks attached themselves to their hosts, they did not 
gorge to repletion and produced uo effect. 
Deaths in Guinea-pigs to which D. venustus luere applied. 
On 22. VII. 1912, one of us (G. H. F. N.) received some eggs of 
D. venustus Irorn Dr C. G. Hewitt, who had received the parent ticks 
from Washington, D.C. The ticks which issued from the eggs were 
placed on various hosts, with the object of raising them to maturity and 
studying their biology. 
20—2 
