366 
Regeneration in Argas persicus 
Second Stage Nymphs. 
In all cases the ticks used in these experiments had been reared 
in the laboratory and their history was known exactly. This precaution 
was vei’y necessary as it is impossible from their appearance alone to 
distinguish with certainty the various nymphal stages. 
Experiment 11. A batch of second stage nymphs 1 was fed on a fowl 
on 13. i. 13. The following day (14. I. 13) four to five articles were 
removed from the second right leg of each individual. Some of the 
ticks were kept at a temperature of 20-30° C., and others at 37° C. 
(a) Second stage nymphs kept at 20-30° C. 
19. 
I. 
13 
1 moulted 
c? 
No regeneration. 
30. 
I. 
13 
2 
¥ and 3rd © 
5. 
II. 
13 
2 
¥ and 3rd © 
6. 
II. 
13 
1 
? 
8. 
II. 
13 
1 
? 
9. 
II. 
13 
1 
<? 
In every ease, the regenerated appendage was 
10. 
II. 
13 
1 „ 
¥ 
‘ about half the normal size, but with the 
12. 
II. 
13 
4 ,, 
¥ and 3 cT <? 
usual number of articles. 
13. 
II. 
13 
1 „ 
¥ 
17. 
II. 
13 
1 
<? 
1. 
III. 
13 
1 
1 
<r ; 
( b ) Second stage nymphs kept at 37° C. 
23. i. 13 
24. i. 13 
25. i. 13 
27. i. 13 
2 moulted s and 3rd © 
6 „ 3 <r <? +3 ? ?' 
3 ,, 2$ S +1 ? 
5 ,, 1 S +3 $ $ + 3rd © 
Regeneration again about half normal size. 
It will be noticed that in one case there was no regeneration, but 
as this animal moulted within five days after the amputation, it is 
probable that the formative substance of the adult limb had been 
removed. 
Fig. 3. Argas persicus, third stage nymph from Experiment 12, showing regeneration 
after removal respectively of—( j 1) tarsus, and ( B ) two, ( C ) three and ( D ) five distal 
articles of second right leg. Ax 33 ; B, C, D x 13. 
1 The sign © denotes nymph throughout. 
