1903.) PHILLIPS—A REVIEW OF PARTHENOGENESIS. 285 
and not by fertilization. It is known that after the eggs are 
hatched, at about the third day, the workers pour into the cell a 
food paste for the nourishment of the larva. Great quantities of 
this are eaten for six days and then the workers cap the cell, and in 
ten or eleven days the bee in its adult form comes out. The cap 
put over the smaller worker cells is flat; that over drone cells, 
arched. vy. Siebold (1868), in answer to this theory, points out that 
sex is differentiated early in insect larve. Herold, for Preris rape, 
was able to tell sex early. On the other hand Meyer did not see 
this in caterpillars only a few days old. Weismann, in Musca 
vomitoria and Sarcophaga carnaria, confirms Herold, but is not so 
sure in the case of Corethra plumicornis.. Leuckart (1865) found 
first traces of external genitalia on the sixth day in Apis. v. Sie- 
bold insists that all embryos (queens included) up to the sixth day 
get food paste (digested chyle paste). The queens continue to get 
this, and from that time on the workers and drones get undigested 
honey and pollen. The food of the drones and workers is therefore 
the same. Landois thinks the drones of unfertile queens and of 
fertile workers are due to scanty nourishment or weak larvee, for in 
Vanessa urtice only males are produced if badly fed. v. Siebold 
(1871) does not find this true in Polistes gallica, for in the spring, 
when food is scarce, workers are produced; and Cuenot (1899) 
denies the truth of all such statements which make the sex depend 
upon nutrition. 
Sanson and Bastian (1868) attempted to repeat the experiments 
of Landois, but in every case when the egg was put in a different 
cell the workers in the hive carried it outside. Never in a single 
case was the egg allowed to develop and they were therefore led to 
deny the experiments of Landois. The reason for their failure, as 
pointed out later by Landois, was imperfect manipulation. They 
cut out the entire bottom of the cell and stuck it in place by melting 
the edge with a hot needle, and this made such a bad job as 
compared with the work of the workers that they cleaned it out. 
Sanson (1868), in opposition to Landois, also cites cases of the pro- 
duction of drones in worker cells. This is now well known, as is 
also the converse, and this fact alone is enough to overthrow all of 
the work of Landois. 
Perez (1878) put a pure Italian queen fertilized by a French 
drone into a hive with pure French workers and no drones. Later 
in the season he collected and examined carefully three hundred 
