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



brought out by measuring the wings. Referring again to the 

 table of the ratios varying according to the length of vein M 2 we 

 find that the vein m varies inversely as the length of M v The 

 length of vein /// represents the ratio of the length of the wing 

 while vein M 2 represents the ratio of the width. Probably most 

 of the drones which have the shortest vein M 2 are those hatched 

 from the smallest cells and the wings could not increase in width 

 and therefore to meet the needs of the animal in making the 

 necessary area of wing for flight the vein ;;/ must be lengthened. 

 On the other hand, those drones hatched from the largest cells 

 would be allowed greater room for the development of vein M 2 

 and vein ;// need not be so long. 



Another fact which seems to indicate this is that those drone 

 pupae which are developing in worker cells are covered over by 

 a very high cap, making the length of their cell much greater 

 than that of the ordinary drone cell. The drones which hatch 

 from these cells are long and narrow when compared with those 

 from drone cells proper. 



The drones in Lot II. were taken from a hive in which there 

 were no drone cells except possibly a very few in the corners of 

 the frame or near the top bar of the frame since all the combs 

 were made on what beekeepers call foundation and the cells were 

 uniformly of worker size. These drones show the least variation 

 since they were all hatched under the same conditions. The 

 drones of Lots I. and III. were hatched in old irregular combs 

 and the tables show considerably greater variability. 



The greatest number of abnormalities were found on the largest 

 drone wings and the throwing in of extra veins is probably caused 

 by the necessity for greater strengthening of the wings. Just 

 how these extra veins arose is not easy to explain. They may 

 be sports, or reversions to an ancestral type, or the result of extra 

 growth-energy or caused by the splitting of normal veins so that 

 it is rather difficult to say just what factors bring about this extra 

 amount of variation. While we speak of these as abnormal veins 

 it must be noted that we do not know whether they are really 

 abnormal or whether they are but the manifestations of a tendency 

 possessed by all bees but which can develop only under certain 

 conditions, just as the ovaries of the workers can develop only 

 when extra room and food are provided. 



