I04' POPULAR SCIENCE MONTHLY. 



roots of the grape, is as follows: A series of par chenogenetic wingless 

 females succeed each other, until at the end of June the last generation 

 of these produces, parthenogenetically, winged females that are capable 

 of migrating. These also produce parthenogenetic eggs of two kinds, 

 small ones from which winged males develop, and larger ones from 

 which winged females arise.* Union of the sexes now takes place and 

 each female lays one egg which gives rise in the following spring to 

 the parthenogenetic wingless female that lives on the root of the 

 grape vine. 



We come now to the much discussed case of the hive bee. There 

 are here three kinds of individuals : the queen which lays all the eggs ; 

 the workers, which are immature females and do not reproduce at all, 

 and the drones or males which fertilize the eggs of the queen. 



It has long been believed that when an egg of the queen is 

 fertilized it gives rise to a female (either queen or worker according to 

 the kind of food given to the young maggot), but if not fertilized the 

 egg gives rise to a male. It has been generally assumed, in accordance 

 with this belief, that all the eggs are alike and will produce males if 

 they are not fertilized, but females if they are fertilized. It is known 

 moreover that the cells of the comb in which the queen deposits the 

 eggs that are to become males are different from the worker cells, and 

 this fact is generally interpreted to mean that the queen is capable of 

 determining the sex of her offspring by allowing or preventing the 

 fertilization of the egg. The sperm which was received by the young 

 queen at the time when she left the hive with a swarm is stored up in 

 a special sac or receptacle with muscular walls and an outlet that 

 opens near the oviducts. It is generally assumed that the queen 

 squeezes out the sperm when an egg that is to be fertilized is laid, but 

 does not do so when a male is to be produced. Some writers have 

 marveled at this wonderful power, that seems almost akin to intelli- 

 gence, by which the queen determines ' at will ' the sex of her offspring, 

 but this may give an entirely exaggerated idea of what takes place, for 

 the act may be a very simple reflex. It has been shown by Drory 

 that if the queen is supplied with an artificial comb containing only 

 drone cells she may be forced to lay in them fertilized eggs that 

 become workers. Conversely, if supplied with worker cells only she 

 will sometimes lay unfertilized eggs in them. This has been inter- 

 preted to mean that there are really two kinds of eggs that are laid by 

 the queen, male and female, and that only the latter are capable, as 

 a rule, of being fertilized. On this assumption we should be forced 

 to conclude either that the queen can determine which kind of egg is 

 to be laid and places it in its proper cell, or that she has a knowledge 



* The small eggs appear to be laid by the smaller winged individuals and 

 the larger eggs by the larger individuals. 



