68 Bulletin Wisconsin Natural History Society. [Vol. 10, Nos. 1 & 2. 
In order to test his hypothesis, Dzierzon carried on a series of 
experiments, in which he crossed two races of different bees. 
According to his contention, the males produced from such a cross 
ought to resemble the mother, since they come from eggs that 
were not fertilized, while all the females ought to be hybrids. The 
results he obtained substantiated his theory. For instance, he 
crossed the virgin Italian queen bee with German drones. The 
males of the resulting progeny, all looked like the Italian males, 
whereas the females were hybrid in character. Many other inves¬ 
tigators working with Ants as well as with Bees have also been 
able to confirm this hypothesis. 
A few exceptions, however, are not wanting. Even Dzierzon 
himself found a case that apparently contradicted his contention, 
and this almost made him retract his former conclusion. 
Perez, in 1878, crossed Italian queens with French males, and 
found that a few of the resulting drones resembled the French 
males. Although this seems a serious objection, still a great many 
workers are suspicious that the female with which Perez worked 
may have been a hybrid, and not an absolutely pure type, as he 
claimed it to be. 
Landois, in 1867, thought he found facts that would overthrow 
Dzierzon’s hypothesis. He placed worker eggs into drone cells, 
and according to him, drones were produced. On the other hand, 
when he placed drone eggs into worker cells, the resulting bees 
were seemingly all workers. He therefore concluded that the sex 
of the resulting individual was wholly dependent on the amount 
of nutrition. 
Sanson and Bastion, in 1868, repeated Londois’ experiments, 
and they showed that whenever eggs were artificially transferred 
from one cell to the other, the workers would always destroy 
these, and clean out the compartment. The queen would then 
deposit the right kind of an egg into the clean cell, and the respect¬ 
ive bee would thereby be hatched. 
In the ant family also, a number of investigators have brought 
forth exceptions to Dzierzon’s theory. Tanner (1893), Reichen- 
bach (1909), and Mrs. Comstock (1903), have observed that in 
certain species (Lasius niger, Atta ), the unfertilized eggs some¬ 
times develop into workers. 
