No.411.] REVIEWS OF RECENT LITERATURE. 231 
sometimes, at any rate, the ascidiozooids of these fully compound 
colonies are noticeably smaller than those of the social forms. 
The specimens studied by Caullery were collected by Lesson in 
1825, locality not given; and by Quoy et Gaimard in 1829 on the 
coast of Australia. Wa. E. RITTER. 
Parthenogenesis of the Honeybee. — Weismann publishes an 
interesting preliminary account of studies on the parthenogenesis of 
bees, which have been carried on in his laboratory for the past three 
years. The conclusions of Dzierzon, confirmed by von Siebold and 
Leuckart, that fertilized eggs always produce workers (or queens), 
and unfertilized, drones (or males), having been in recent years called 
in question by practical bee culturists, Weismann deemed it impera- 
tive to have the question reinvestigated, especially in view of its 
great theoretical importance. He accordingly induced one of his 
students, Dr. Paulcke, to undertake the problem, and the studies thus 
begun are now being completed by Dr. Petrunkewitsch, another of 
Weismann's students. 
One of the most energetic of the recent opponents of Dzierzon's 
conclusions has been the editor of the Nördlinger Bienenzeitung, F. 
Dickel of Darmstadt. His experiments seemed to prove that nor- 
mally a// eggs are fertilized. Eggs which had been laid in drone 
cells were transferred to worker cells, with the result that they devel- 
oped into workers, and vice versa. Dickel argued, further, that the 
evidence of von Siebold and Leuckart, based on the microscopic 
examination of the eggs, could not be regarded as definitive, now 
that we know more precisely the phenomena accompanying fertiliza- 
tion. These observers had not examined eggs immediately after they 
were laid, but only after the lapse of from one to twelve hours. But 
it is now known that spermatozoa lose their thread-like form within 
a few hours after the eggs are laid, and are succeeded by the sperm 
nucleus and sperm aster ; in fact, it has been recently asserted that 
this metamorphosis takes place in bees' eggs within fifteen or twenty 
minutes after the entrance of the spermatozoóün into the egg. 
Nevertheless, there is no ground to doubt, says Weismann, that 
von Siebold saw seminal filaments (even two to four in a single egg), 
for Blochmann, making use of the sectioning method, has seen the 
same, and Petrunkewitsch now confirms the observation ; but these 
could have been seen only in von Siebold's freshest eggs, all of which 
! Weismann, A. Ueber die Parthenogenese der Bienen, Anat. Anzeiger, Bd. 
xviii, Heft 20-21, PpP- 492-499, December 5, 1900. 
