EXPERIMENTAL INQUIRIES. 269 
The physiological difficulty, however, is not here ; 
there is no mystery about the maternity of the eggs; 
for we constantly find, even in the higher animals, 
that eggs may be laid without impregnation. This, as 
is well known, is the rule in fishes and some reptiles. 
Its occurrence in birds is familiar to poultry-keepers ; 
and a ‘parrot confined for years in a cage occasionally 
presents her astonished owner with an egg.* The 
curious thing is that the removal of the queen-mother 
should at once stimulate the imperfect ovaries of the 
workers into activity, that eggs laid under such cir- 
cumstances should hatch at all, and that hatching 
they should produce drone brood only. 
Whenever I have had an opportunity of examining 
the comb of a secondary nest, built after the removal 
of the queen, I have invariably found whatever pupee 
it might contain to be of the male sex. This fact, 
inexplicable on other grounds, is at once explained on 
the principle of Parthenogenesis as laid down by 
Siebold. And, as far as my own observations go, I 
have every reason to believe that wasps conform to 
this law generally in the same way as honey-bees. 
But this whole matter still needs examination by other 
observers and by different modes of imquiry; for, 
apart from the general facts, there are other questions 
waiting solution. For instance: Is it certain that the 
workers do not ever lay eggs when the queen is with 
them? and, in such case, what becomes of these 
eggs? Again: remembering that the last laid eggs 
of the solitary bees produce males,f how far is the 
* ‘Harvey’s Works,’ translated by Willis, Sydenham Society, p. 186, 
contain the fullest information on this subject. 
+ Wood. ‘ Homes without Hands,’ p. 179, 
