CXXVi 
than the males, on account of their more complete development, he 
forgets that in the hive bee the queen comes to maturity in sixteen 
days, while the workers require twenty-one, and the drones twenty- 
four. Of course if Dr. Landois were correct in his statement that the 
sex of an insect depends upon its nourishment, it follows that it must 
be undetermined even until some time after the hatching of the egg. 
No one indeed has yet ascertained that, in the case of the bee, the 
sex is determined in the embryo, but from analogy it is most probable 
that this is the case. 
Moreover, as Prof. Siebold has pointed out (Zeit. f. Wiss. Zool. 
1867, p. 525), the food of all bee-larvz is the same for the first six 
days, and that of the drones and workers even longer—a fact which 
seems fatal to M. Landois’ theory. M. Siebold expresses, in courteous 
language, a doubt, which I think most naturalists will share, whether 
there is not perhaps some mistake in M. Landois’ experiment. 
In the same number of the ‘ Zeitschrift” M. Kleine also makes some 
remarks on M. Landois’ theory. He also points out that the food of 
workers and drones is identical; and as regards the difficulty pre- 
sented by the crossing of the Italian bee with an ordinary drone, he 
observes that Italian drones under any circumstances vary consider- 
ably, and that even when of pure breed many of them cannot be dis- 
tinguished from the northern variety. He adds, moreover, that before 
the introduction of the Italian variety, drones closely resembling 
Italians sometimes made their appearance. 
Moreover, as long ago as 1862, Berlepsch had performed Landois’ 
experiment of transferring eggs, but with very different results. He 
took six eggs out of drone-cells and placed them in ordinary cells. 
Two perished, but four produced drones. Again he transferred six 
other eggs from ordinary cells into drone-cells. One perished, the 
other five produced larve which reached a certain size, and were then 
destroyed by the bees. Berlepsch examined them and found that 
they were males. It is evident, therefore, that the transference of eggs 
from male cells to female cells, or vice versd, does not have any effect 
on the sex. 
M. E. Bessels * has also taken great pains to settle this interesting 
question. In spite of several attempts, made with the greatest care, he 
was unable successfully to perform the transference experiment. In 
every case the bees removed the obnoxious egg. By varying the experi- 
ment, however, which he did in a very ingenious manner, he induced the 
* Zeits. f. Wiss. Zool., Vol. xviii. Pt. 1. 
