226 
SIEBOLD, ON PARTHENOGENESIS. 
The general facts of the case having been made out by the 
apiarians^ both Leuckart and Von Siebold determined, if 
possible_, to test these views by the aid of the microscope. 
Both observers were aware that in certain stages of the fe- 
cundated germ-cell, the filaments of the sperm-cell may be 
observed. If, therefore, the facts stated by Dzierzon and the 
other apiarians were true, the sperm-filaments ought to be 
detected in the eggs of the female or worker bees, whilst 
they would be absent from those of the male or drone bees. 
Leuckart was not successful in examining a large series of 
eggs, but he gives the following result of his investigation : 
" On two occasions only I met with some undoubted seminal filaments 
upon the micropyle of bees' eggs ; on one occasion a single filament, on the 
other several, four or five (and yet I have most carefully examined more 
than fifty bees' eggs !). On both occasions it was upon worker-eggs that I 
found the seminal filaments. In drone-eggs I have never been able to 
distinguish a seminal filament, although I probably examined more drone- 
eggs than worker-eggs, and amongst these such as had been laid at the 
utmost a quarter of an hour previously." 
Von Siebold was more successful. He says — 
"After various vain endeavours to render the interior of the bee's egg 
accessible to the inquiring eye, I came at last to the idea of employing an 
artifice, which I had soon acquired by practice, and which allowed me to 
survey at least a portion of the inner space of the bee's eggs with great 
clearness and tranquillity. I crushed a bee's egg quite gently with a very 
thin glass-plate, and so that it was ruptured at its lower pole, opposite to 
the micropylar apparatus, and the yelk gradually flowed out at this spot, by 
which a clear empty space was produced at the upper pole within the 
micropylar apparatus, between the egg-envelopes and the yelk which was 
retiring downwards. I directed my attention very particularly to this 
empty space, which I saw slowly produced under the microscope during 
the effusion of the yelk. The production of such a preparation of course 
was not always successful, for sometimes the yelk flowed out of the ruptured 
envelopes, without the production of this empty space ; the yelk also 
remained diffused in the upper part, and allowed of no certain judgment 
as to the presence or absence of seminal filaments. An error in crushing 
the egg, a little too much pressure upon it, or perhaps also a peculiar, less 
tenacious consistency of the yelk, probably caused the contents of the yelk 
upwards against the micropylar apparatus." 
Of the result of his examination of the female eggs he 
says — 
"Amongst the fifty-two female bee-eggs examined by me with the greatest 
care and conscientiousness, thirty furnished a positive result ; that is to say, 
in thirty, I could prove the existence of seminal filaments, in which move- 
ments could even be detected in three eggs. Of the other twenty- two eggs, 
twelve were unsuccessful in their preparation. At the same time I may also 
indicate particularly, that the observations with positive and negative results 
followed each other quite irregularly, but alternating at very short intervals, 
to retire in every direction 
therefore also to press 
