458 
Arfijicial Partlieiuxjenesis in Ticks 
The 10 larvae, progeny of $ 3, were placed on a ram 31 days after 
they emerged, but none of them were recovered. 
None of the 19 unfertilized $s became as fully gorged as did fertihzed 
$s; their bodies were all flattened dorso-ventrally when they abandoned 
the host. In only 4 ?s (Nos. 1, 2, 3, 6) did the length x width approach 
that of fertilized fully gorged ?s. The measurements of 12 such ?s are 
appended in the following dable for comparison. The two sets of 
measurements do not show the main difference which is in the dorso- 
ventral direction. 
Size attained by 19 unfertilized and by 12 fertilized ?s, the latter- 
chosen at random from a large stock: 
Unfertilized ?s. Fertilized $s. 
Length X 
Length X 
No. of clays 
? 
Breadth 
No. of (lays ? fed on host 
? 
breadth 
? fed 
No. 
in mm. 
No. 
in mm. 
on host 
4 
6-5 X 4-0 
52 days 
1 
13-5x9-0 
4-12 days 
15 
7-5x5 
69 „ 
2 
14-5 X 9 
?? 
19 
8-5x5 
91 „ 
3 
14-5x9-5 
12, 14 
9-5 X 6 
57, 69 days 
4 
15-0 X 10 
11, 17, 18 
10 X 0 
57, 84, 90 days 
5 
15-0 X 10 
•> 
10, 13, 16 
11 x7 
57, 69, 80 
6 
15-0 X 10 
jf 
9 
11-5 X 8 
57 days, oviposited 
7 ■ 
15-0x11 
>• 
7, 8 
12x8 
57, 57 days, one oviposited 
8 
15-5 X 10 
5 
12x8-5 
54 days, oviposited 
9 
16-0 X 10 
99 
6 
13 X 8 
57 days 
10 
16-0x10 
99 
1,3 
13 X 9 
25, 30 days, both oviposited 
11 
16-0 X 10 
99 
2 
15x10 
25 days, oviposited 
12 
170x11-5 
99 
It appears from the foregoing table, that unfertilized ?s require to 
reach a certain size in respect to engorgement before they will in most 
cases lay any eggs. The length of stay on the host exerts no influence; 
the essential factor is the amount of blood which the tick has succeeded 
in imbibing. 
