368 Regeneration in Argas persicus 
( d ) Four distal articles of second right leg amputated 6. V. 13. 
23. v. 13 5 moulted 2 $ s 4-3 ? $ | -r, ,. ,,, 
l Regeneration as m (6). 
24. v. 13 1 ,, <? i 
(e) All legs amputated 6. v. 13. 
27. v. 13 2 moulted 2 <? <r 
28. v. 13 1 0 
29. v. 13 1 <? 
31. v. 13 1 © 
' In every case the legs were regenerated with, 
the normal number of articles, but were 
about two-thirds to three-quarters normal 
, size. 
In addition to the above, a few experiments were undertaken in 
order to find out the minimum time in which second stage nymphs 
could regenerate their limbs. Owing to lack of material we have been 
unable to carry out these experiments as completely as we should have 
wished, but the results obtained were concordant with those obtained 
with the first stage nymphs. 
Summary of results. 
In all stages of Argas persicus, if the leg is amputated sufficiently 
long before moulting, regeneration takes place, but the regenerated 
appendage is practically always less than normal in size, although 
possessing the usual number of articles. In no case was there any 
evidence of atavistic regeneration. Moreover, when the legs of a larva 
were amputated it invariably regenerated nymphal legs. 
On comparing the periods elapsing between feeding and amputation, 
and amputation and moulting, respectively, it will be found that in each 
stage there is a minimum post-amputation period, beyond which no 
regeneration takes place. It is rather curious that this period is rela¬ 
tively longer in the case of the larvae than in the other stages. 
It should be noticed that amputation of one or two articles causes 
a reduction in all the remaining articles of the leg. The results were 
very striking in the experiments with the first stage nymphs, in which 
we amputated respectively one, two, three, four and five articles, yet in 
all these cases the regenerated limb was normally proportioned though 
reduced in size. 
We must except from these conclusions those cases in which the 
appendages were amputated about the end of the pre-amputation 
period. In these examples the regenerated appendages were frequently 
much reduced in size and also in the number of articles. 
