E. Hindle 
261 
(e) Dark $ x white 34 eggs were laid of which 5 hatched and 
4 became adult. (Female brood.) 4$$ 
(/) White (J X,white $; 63 eggs were laid of which 48 hatched 
and 32 became adult. (Female brood.) 32$$ 
(g) White ^ x white $; 51 eggs laid of which 29 hatched and 25 j 17 c?cJ 
became adult. (Mixed brood.) (8$$ 
In the above series of experiments it will be noticed that three of 
the broods were entirely male; two, female; whilst three were mixed 
broods in which the number of males was approximately double the 
number of females. The results of experiments {a) and (a 1) show that 
the same male can produce both male and mixed broods. 
Exp. 2. Broods from lice of known parentage, taken from the 
above-mentioned reared broods. The nature of the brood the parent 
came from is indicated in brackets, as also the number of the experi¬ 
ment^. 
(®) (?(<^c??) ?(cd?)' 17 adults were reared. (Mixed brood.) 
i 3$$ 
(^) d(^c?(?) X $(C(J?)- 34 adults were reared. (Female brood.) 34$$ 
{^) (? (^dd) X $ (C(J$). 48 adults were reared. (Female brood.) 48$$ 
In this series only three broods were reared and an accident to the 
incubator prevented further experiments with this series. 
Second Series (17. i. 14) 
First Generations. Broods from lice of unknown parentage^. 
(1) Medium d x white $; 45 nymphs hatched of which 27 became 
adult. Male brood. 27 dd 
(2) White d X white $; 58 nymphs hatched, of which 45 became 
adult. Female brood. 45$$ 
(3) White (J X white $; 38 nymphs hatched, of which 32 became (31$$ 
Eidult. Female brood (?). i Id(-) 
(4) White d x medium $; 16 nymphs hatched, of which 9 became 
adult. Female brood. 9$$ 
1 For example, $ (c <5$) x (6 cJ(J) signiBes that the female came from the mixed 
brood of (c) in experiment 1 , and was crossed with a male from the male brood (b) of the 
above series. 
* The terms dark, medium and white are used to indicate roughly the pigmentation 
of the lice. Details of the colouration of broods will be given later. 
