290 PHILLIPS—A REVIEW OF PARTHENOGENESIS.  [0ct. 16, 
theory in regard to the determination of sex in the bee and he has 
some supporters, although the number of these seems to be decreas- 
ing. His views are briefly the following: Eggs laid by unferti- 
lized queens or fertile workers produce drones, but these differ 
from the drones of a colony with a fertile queen. The egg before 
fertilization contains only male elements, the sperm cell only 
female, and after union of the two these are equally balanced. A 
fertile queen can lay only fertilized eggs since she cannot withhold 
sperm cells. The workers, in crawling over the brood cells just 
after the eggs are laid, pour out a secretion which penetrates the 
chorion of the egg. The wax, in the formation of brood cells, is 
kneaded in the mouths of workers and is impregnated from the 
salivary glands with a secretion characteristic of drone or worker 
cells, and this determines the kind of cell made and consequently 
the nature of the secretion poured out over the egg when laid. 
The two sexes are equally balanced in the newly-laid egg and the 
workers pour out a secretion from one of two glands in the head, 
the secretion from one causing the egg to develop into a male; of 
the other, into a female. The secretion of the ‘‘ salivary ’’ gland 
of the workers is comparable to a sexual act and probably pro- 
duces similar emotions. Sex cannot be determined by mere size 
of cell or by food. These glands have been observed in the queen 
in a rudimentary state and in wasps. It is further claimed that 
experiments (performed by Dickel himself) on hybrid hives have 
clearly shown paternal characteristics in male offspring. 
Weismann and his students, Petrunkewitsch and Paulcke, have 
pointed out the errors in this theory and, from work of their own, 
strongly reaffirm the view of Dzierzon, that sex is here determined 
by fertilization. ‘ 
OTHER CASES OF PARTHENOGENESIS. 
Classification.—Parthenogenetic development manifests itself in 
a variety of ways and many synonymous terms have been applied 
to the different kinds of parthenogenesis. The following classifica- 
tion will serve to make clear the relations of the different phenomena 
to one another and to show the synonymous terms used : 
PARTHENOGENESIS (Agamogenesis). 
1. Partial. 
Development to early cleavage or larva. 
e.g., Vertebrates (?) and Echinoderms. 
