Biology of Ixodidae 
Longevity of unfed R. sanguineus. 
Larvae. 
Progeny of 
? No. 
Emerged from 
eggs on 
Number of days 
larvae lived 
unfed 
Larvae maintained 
in corked tubes 
at a temperature 
of 
— 
9. xn. 1913 
97 
ca. 12*" C. 
19 
16. III. 
153 
ca. 15° C. 
17 
15. m. 
161 
— 
11 
14. III. 
162 
— 
3 
14. III. 
174 
— 
4 
13. III. 
180 
— 
7 
13. III. 
187 
— 
26 
17. III. 
201 
— 
15, 21-24 
16. m. 
202 
—. 
25 
22. m. 
203 
„ 
10, 12 
14. m. 
204 
— 
5 
13. ni. 
205 
— 
16 
16. III. 
222 
— 
13 
14. in. 
231 
— 
18 
14. in 
232 
— 
14 
16. ni. 
244 
— 
20 
14. in. 
253 
— 
Nymphs. 
2ncl gen. 
from $ 6 
Nymphs 
emerged ou 
.3. vn. 1914 
Number of days 
nymphs survived 
unfed 
2 out of 55 survived 97 
days. (Of 58 gorged 
larvae only 3 failed to 
undergo metamor¬ 
phosis to nymphs.) 
Nymphs 
maintained 
at 
22° C. 
Adults. 
Date of Examined 
emergence on day 
10. XII. 1913 360 
18 V. 1913 569 
i 
f 
1 
Maintained at room temperature, 
i.e. ca. 15° C. 
Out of a total of 132 adults there were 130 alive 
(59 71 ?) and 2 dead (2 59 © had faded 
to undergo metamorphosis. 
Out of a total of 575 adults there were 491 alive 
(170 <^, 321 $) and 84 dead (54 d*, 30 $), only 4 @ 
had failed to undergo metamorphosis. 
