Apiary Experiments. 7 



measurements. A large number of *plaster casts of comb on differ- 

 ent foundations and of the foundations themselves were made, and 

 then cut in different directions as shown in Plates 2 and 5. This 

 made it possible to cut the wax of the different cells so that the 

 thickness could be measured. A large number of measurements 

 were made and tabulated, but the variations are so great in thick- 

 ness of both midribs and cell walls in all kinds of comb that I have 

 thought it not worth while to include the table here, but will state 

 the general results. 



t The common range in thickness of the midrib in naturally 

 built worker comb was found to be between .08 and .16 millimeters.J 

 In drone comb the common range was between .12 and .20 milli- 

 meters. None of the midribs of comb built on artificial foundations 

 averaged as thin as the natural midrib in worker comb. In some 

 cases those from thin and extra thin super foundations, and the 

 "1899" deep-cell foundation approximated it closely. Where the 

 midrib of a foundation is not thicker than about .17 millimeters, 

 the bees seem not to thin much if any, though they go over the sur- 

 face with their mandibles and scrape it so that it loses its tranpar- 

 ency. 



■It was also noticed that the midrib of any comb was thicker near 

 its attachment, at the top, sides or bottom, than at some distance 

 from these attachments. Illustrations of this may be seen in Plates 

 2 and 3. Fig. c of the latter plate shows a cut through the comb 

 of a pound section made from side to side. 



The heavier midrib and cell walls in drone comb are necessary 

 to give it the same strength as worker comb, because the larger the 

 cells the fewer the number, and the smaller the amount of wax re- 

 quired to build them to a given thickness. 



Sections of natural worker comb are shown at 6, c, and e, and the 

 lower halves of a and g of Plate 3. Drone comb is shown in the 

 lower part of i in Plate 2, and in f of Plate 3. 



The midrib of comb built on " 1898 " deep-cell foundation 

 was very irregular in thickness, for the reasons; already given, and 

 averaged about the same as drone comb. See Plate 4, Figs. cand/. 

 Medium brood foundation also gave wide variations in the amount 

 of thinning. 



At Plate 2, d and e, are two of the best thinned samples I have 

 seen, though little drawn. At/, Plate 5, is a sample of fully drawn 

 comb on this foundation which has the midrib thinned but little. 



At/, Plate 2, is shown a section of super foundation obtained 

 from Mr. Elliott, of Denver, and at /i is a section through comb on 



* I got this idea from Mr. E. K. Root, Editor of "Gleanings in Bee Culture." 

 t I have not found any samples of natural comb with as heavy Cell walls as 

 those shown on page 69 of "A, B, C of Bee Culture," Figs. 1 and 2. 

 X Reduce millimeters to inches by dividing by 25. 



