446 
Biolog}! of Ixoflidae 
Longevity of R. bursa ivlien unfed. 
Larvae. The ticks were maintained in corked tubes placed in semi¬ 
darkness in a cupboard at room temperature in the Quick Laboratory. 
Progeny of 
Pate when larvae 
Number of days 
ngle ¥ s N os. 
emerged 
larvae lived unfed 
3 
4. vn. 1912 
352 days 
4 
4. vn. 
330 
5 
5. vn. 
343 
6 
5. vn. 
358 
8 
7. vn. 
363 
10 
7. vn. 
349 
11 
11. vn. 
337 
12 
10. vn. 
360 
14 
12. vn. 
322 
15 
26. IX. 
276 
16 
27. IX. 
268 
17 
24. X. 
225 
18 
17. X. 
232 
19 
26. X. 
196 
20 
26. X. 
182 
21 
23. X. 
228 
22 
26. X. 
222 
23 
21. X. 
240 
24 
19. X. 
173 
25 
24. X. 
182 
26 
21. X. 
270 
27 
24. X. 
267 
28 
29. X. 
233 
29 
19. X. 
243 
These data appear somewhat misleading, for they relate to the last 
signs of life exhibited by a very few survivors amongst roundly 5000 
to 7000 larvae composing the jri’Ogeny of 24 separate females. Even 
in the broods which survived for nearly a year the majority of the 
larvae usually ceased to be really active after about 200 days. Never¬ 
theless the progeny of $ No. 20 were successfidly raised after a starvation 
period of 182 days. 
Nymphs. The longevity of the nymphs remains to be determined. 
Adults. 
Examined after 
343 days and found active. 
641 days and found aU dead 
364 days found all dead 
279 days and found roundly 
J of the (Js and J of the 
$s dead. 
Kemarks 
1st generation. The lot comprised 1817 
adults (824 993 $). 
2nd generation. 
3rd generation. Out of 3463 gorged 
nymphs, there emerged 3363 adults, 
100 nymphs having faded to imdergo 
metamorphosis. The adults comprised 
a total of 1696 and 1667 $ of which 
460 cJ and 565 $ were dead. 
Date of 
emergence 
19. n. 1912 
7. I. 1913 
23.11. 1914 
