E. Hindle and N. Cunliffe 
359 
ii. Second right leg amputated 10. iv. 13: 
14. iv. 13 1 moulted No regeneration. 
15. iv. 13 4 ,, 2, no regeneration ; 2, small pointed knob present. 
16. iv. 13 1 ,, A two-jointed rod present. 
iii. Third right leg amputated 10. iv. 13 : 
14. iv. 13 6 moulted No regeneration. 
iv. Hind pair of legs amputated 10. iv. 13: 
14. iv. 13 4 moulted No regeneration. 
15. iv. 13 2 
v. Two hind pairs of legs amputated 10. iv. 13: 
15^. iv. 13 3 moulted 2, no regeneration ; 1, left side, no regeneration: right 
side, second appendage, three-jointed rod without claw; 
third appendage, four-jointed rod, with rudimentary 
claw. 
16. iv. 13 2 moulted In both cases two pairs of half-size legs regenerated, the 
articulations somewhat indistinct. 
vi. All three pairs of legs amputated 10. iv. 13 : 
14. iv. 13 1 moulted No regeneration. 
4 dead 
15. iv. 13 1 moulted No regeneration. 
In this latter series more of the ticks showed signs of regeneration 
than in the case of those kept at 30 C., but the results are not definite 
enough to permit of conclusions. 
In both series examples from each of the experiments were fed and 
allowed to moult to second stage nymphs. In every case the limbs then 
regenerated and varied from two-thirds to three-quarters the normal 
size, but were perfectly proportioned. 
In all the above experiments the almost total absence of any 
attempt at regeneration in the larval stage is very striking, but it might 
be explained as the result of the comparatively short time elapsing 
between the amputation and the moult. 
We therefore performed a second series of experiments in which we 
cut off the legs whilst the larvae were still feeding, and as will be seen 
we obtained quite different results. 
Experiment 6. A batch of larvae was put on the fowl on April 5. 
Three days later some of the legs of sixteen ticks were amputated 
whilst still on the fowl. Three of these ticks dropped off gorged two 
days later, whilst the remaining thirteen dropped off the following day. 
Owing to the difficulty of operation, it was impossible to remove any 
particular articles and therefore the extent of the amputation could only 
be determined later and varied considerably in different individuals. 
