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THE AMERICAN NATURALIST [Vol. L 



drones come from the mother, which is in accord with 

 Dzierzon's theory that the drones arise from unfertilized 

 eggs. This is further established by the following evi- 

 dence. The daughters (queens) that come from Italian 

 queens by Carniolan drones give rise to two kinds of 

 drones in equal numbers, viz., Italian and Carniolan, which 

 is the expected result, since such daughters are hybrid and 

 are expected to produce two kinds of eggs. Reciprocally 

 also the daughters from Carniolan queens by Italian 

 drones produce two kinds and only two kinds of drones in 

 equal numbers. The result also shows that Mendel's law 

 applies to the queen bee. Cuenot has recently recorded 

 the appearance of some drones in hybrid hives that are 

 intermediate or even like the father, but since the possible 

 production of drones by hybrid workers was not excluded, 

 at least so far as the published evidence goes, these spo- 

 radic cases can not be used to disprove the maternal in- 

 heritance of the drones. 



Boveri has discussed certain cytological possibilities in 

 relation to the gynandromorph bees that are of interest. 

 His work, and that of Herbst on sea-urchin embryos, had 

 shown that haploid nuclei have only half the volume of 

 diploid nuclei. It might have been anticipated therefore 

 that the nuclei (and cells) of the drone bee would be half 

 the size of those of the queen or of the worker bee, but a 

 study of the cells of drones by Oeninger had already shown 

 that their nuclei are as large as are those of the workers 

 which have the diploid number of chromosomes. It is not 

 possible therefore to determine by microscopic study of 

 nuclear size whether or not the male parts of gynandro- 

 morphs come from a single nucleus. 



Boveri points out that, since the nucleus of the egg of 

 the bee, if not fertilized, proceeds to divide, it is improb- 

 able that the division center is brought in by the sperm, as 

 appears to be the case in so many other eggs. Nachts- 

 heim^s observations confirm, he believes, this interpreta- 

 tion in the bee; for, according to Naehtsheim, three to 

 seven or more nuclei enter but only one of these fuses 

 with the egg nucleus. The others move out into the egg, 



