A Biometrical Study of the Influence of Size of Brood Cell Upon the Size and Variability of the Honeybee (Apis mellifera L.) by Roy A. Grout, 1931

The keeping of bees for the pleasure derived from them and for the benefits and profits arising from their products has been an important vocation and avocation for many centuries. Due to the interest of naturalists and observers, the study of the size, shape and type of the cells of a colony dates back several centuries before Christ. The first outstanding study of the effect of the size of cell upon the size of the honeybee did not occur until 1791 when Hubor (32), at the suggestion of Bonnet, succeeded in raising worker bees in drone cells and drone bees in worker cells. In the former case, he did not notice any change in the size of the emerging worker bee, but in the latter experiment he observed that the emerging drones were smaller. This study initiated a series of observations of this phenomenon but only Zarudski, according to Michailov (43), noticed any increase in the size of the emerging bees. Martynov, Tuenin and Michailov recently have conducted microscopical investigations concerning this matter and all agree in their conclusions that the bees reared in drone cells are larger than their worker bee sisters.

About the beginning of the 20th century, several controversies arose which concerned the size of the honeybee and its dependability upon the size of the cell. The first of these concerned the effect of the age of the comb upon the size of its emerging bees. It is unquestionable that this had a great influence in bringing about the large cell controversy in France and Belgium. At about the same time, the problem of enlarging the bees became an important issue here in America and a long discussion concerning length of the honeybee probescis and its relation to pollination and honey production ensued. The following is a discussion of the above three controversies in the order given.

The controversy concerning the effects of the age of the brood comb upon the size of the emerging bees emanated from the supposition that the cast-off pupa skin, excrement and varnishing of the cell with the emergence of each generation tended to decrease the size of the cells. Many of the more prominent figures in the beekeeping profession took part in this controversy, the majority contending that the age of the comb had no effect upon the size of each succeeding generation due to the lengthening of the cell by the worker bees. As in the case of the worker bees reared in drone cells, microscopical investigations by Tuenin and Michailov showed that the cells of old combs were smaller and that there was an accompanying decrease in size of the emerging bees.

Baudoux (7) in Belgium was the first to conceive the idea of using a larger size of cell by increasing the size of the cell base on the artificial foundation given to the bees. Others who have worked along this line are Pincot, according to Gillet-Croix (26), and Lovchinovskaya (39). The work of the first two has not been of a very scientific nature but convincing to the extent that manufacturing houses are selling foundation with enlarged cells and claiming good results for the use of same.

The problem of raising larger bees and especially bees having longer tongues or a greater tongue-reach has been a topic of great interest in this country since the beginning of the present century. This problem reached its peak of interest when Root (59) observed one of the colonies in his apiaries foraging on the long corollatubes of the red clover (Trifolium pratense). He later sold on the market queens from the mother of this same colony with the guarantee that they would produce bees having tongues long enough to acquire nectar from red clover. However, these unusual characteristics were soon lost.

Honeybees are not native to America. Since their introduction into this country, an extensive hybridization has taken place. Recently, methods for controlling the mating of the queen bee by artificial means have been discovered but such methods, to date, cannot be used by the commercial beekeepers due to the intricacy of the technique and the low degree of impregnation.

In consequence of the difficulties encountered in controlled breeding and due to the increased use of foundation having enlarged cells in France and Belgium, the attention of a foundation manufacturer in this country has turned to the study of the effects of the enlarged cell upon the size and productivity of bees.

In this paper, a study has been made of the effect of cell size upon the size of the honeybee. No attempt has been made to study the production of colonies reared on large cell foundation due to lack of time, since an experiment of that kind should cover a period of two or more years. The writer realizes that while the crucial test for the commercial use of enlarged foundation is honey production, the present study should be a strong indication toward that end.