364 
Regeneration in Argas persicus 
The small extent of the regeneration in the first three ticks is note¬ 
worthy, but is explicable on the comparatively short time elapsing 
between amputation and moulting (Fig. 2, F). 
(g, h, i, k) In this series, the first, second, third and fourth right 
legs respectively were amputated on 3. iv. 13. 
The results were uniform ; in every case the regenerated appendage 
was normally jointed but only about three-quarters the size of the 
corresponding leg on the opposite side. The regenerative power 
possessed by each limb seems to be approximately the same. 
(I, m, n, o) In this series, respectively the fourth pair, the third 
and fourth pairs, the three hind pairs and finally all the legs were 
amputated 3. IV. 13. The results were uniform; even in those in¬ 
dividuals which had lost all their legs, normally jointed limbs were 
regenerated, but their size varied from two-thirds to three-quarters that 
of the normal limbs. 
Experiment 9. The results of Exp. 8, (c) to (_/), show that no 
matter how many articles are removed, the regenerated limb is always 
normally proportioned but reduced in size; in other words, not only 
those articles which have been removed, but also the remaining articles, 
partake in the general reduction that ensues. This seemed of such 
importance that we performed a more extensive series of experiments 
with larger numbers of ticks. In one batch of nymphs, only the two 
distal articles were removed, whilst in the other the leg was cut off as 
near to the coxa as possible. Again we obtained results which 
thoroughly confirmed our previous observations. In every case the 
leg regenerated as a whole, not merely renewing the missing articles. 
Perhaps the regenerated legs were slightly smaller in the case of those 
ticks which had had more articles removed, but the differences were 
very insignificant and generally the legs appeared to be of about the 
size. 
Experiment 10. As the period elapsing between feeding and moulting 
is so important in the larval stage, we tried to determine whether it 
was equally so in the case of the nymphs. With this object, on 2. IY. 13, 
a number of first stage nymphs were allowed to engorge themselves 
and on 4. iv. 13, and each successive day up to 11. iv. 13, the second 
right legs of a certain number of individuals were removed. As in 
many cases the moulting was unaccountably delayed, it is necessary, 
for a clear understanding of the significance of each example, to give 
the number of days elapsing between feeding and amputation, and 
between amputation and moulting. 
