COMPARATIVE VARIABILITY OF DRONES AND 

 WORKERS OF THE HONEY BEE. 1 



D. B. CASTEEL AND E. F. PHILLIPS. 



INTRODUCTION. 



According to the theory of germinal variation it would be 

 concluded that the workers of the honey bee, Apis uuilifica, 

 being produced from fertilized eggs, would show more variation 

 than would the drones which come from parthenogenetic eggs. 

 This variation would be manifested by coloration and by relative 

 size of parts, and it might be expected that a series of measure- 

 ments made on like parts of drones and workers would show a 

 smaller degree of variability for drones than for workers. To test 

 this fact a series of measurements have been made and the results 

 tabulated. 



Owing to the difficulty of measuring the extent of coloration 

 on the segments of the abdomen this could not well be used for 

 this work, and so a series of measurements on the wings were 

 chosen although coloration is practically the only difference 

 usually observed between the varieties of Apis mcllifica. 



The wings are also desirable for other reasons. They are of 

 classificatory importance in systematic work, do not shrink when 

 preserved in alcohol and are easily examined with a microscope 

 by simply clipping off the wing and mounting in alcohol on a 

 slide. They also give more accurate results since the extent of 

 coloration would vary according to the retraction of the seg- 

 ments of the abdomen in preserving and it would be practically 

 impossible to get the individuals normally extended in all cases. 



The reason for taking up this work was rather indirect and 

 should perhaps be stated since the results throw some light on 

 a widely separated line of work. Perez 2 (1878) took an Italian 

 queen fertilized by a French black drone, and after some time 

 examined 300 drones from this queen. As the queen was pure 



1 Contribution from the Zoological Laboratory of the University of Pennsylvania. 



2 Perez, J., " Memoire sur la ponte de 1'abeille reine et la theorie de Dzierzon. 

 Ann. Sci. Nat., 6 Ser., Zool., T. 7, 1878. 



18 



