8 Bulletin 54. 



this foundation. The midrib averages about .17 miUimeters in 

 thickness, or fully as heavy as the midrib in drone comb. The 

 upper half of i in this plate is also on this foundation, and the mid- 

 rib is rather heavier than the midrib of the drone comb which the 

 bees built, shown in the lower half of the figure. 



At; of Plate 2 is shown a section of thin, and at I of the extra 

 thin super foundations. The two differ chiefly in that the former 

 has rather heavy cell walls, while the extra thin has almost no 

 walls. At jfc is a section showing partially drawn comb on the thin 

 super foundation, and at g, Plate 5, is a sample of fully drawn comb 

 on the extra thin foundation. It will be noticed that the midribs 

 of the comb samples ts'uilt on these foundations are in most cases 

 nearly, if not quite, as thick as in the foundations themselves. At a 

 of Plate 3 is a section through comb, the upper two-fifths of which 

 was built upon the thin super foundation and the lower three-fifths 

 is natural. The midrib of the foundation seems not to have been 

 thinned at all, and contrasts plainly with the midrib of the portion 

 that was built entirely by the bees, and also with the midribs of 

 figures h and c of the same plate, both of which represent natural 

 comb. 



At g of Plate 4 is shown a section of the beautiful "1899'' deep- 

 cell foundation, as I have termed it, that is manufactured by Mr. 

 E. B. Weed. At h of the same plate is shown comb slightly worked 

 on this foundation, and at a of Plate 5 is shown fully drawn comb 

 on the same. Here again it will be noticed that the midrib is 

 scarcely if at all thinned, and is as heavy as that of drone comb. 



The evidence thus obtained by measuring the thickness of the 

 midribs of foundations and of the comb built upon them bears out 

 the results obtained by weighing, namely, that heavy foundations 

 have their midribs thinned some, usually much, by the bees when 

 they build comb upon them ; but these are not thinned, in any case, 

 to the lightness of natural worker comb. If the midrib is not 

 thicker than .17 millimeters — .068 of an inch — the bees thin it little 

 if any; if the midrib is much thinner than the normal, the bees are 

 likely to thicken it by the addition of wax, making it much heavier 

 than in natural comb. 



DOES THE USE OF AKTIFICIAL FOUNDATIONS RESULT IN THICKER 

 CELL WALLS IN THE COMB ? 



It is evident that a slight thickening of the cell walls increases 

 the weight of the comb more than the same thickening of the mid- 

 rib. *Cheshire estimated that the area of the cell walls of worker 

 comb one inch thick is fully ten times that of the midrib upon 

 which they are built. If this be true (and the difference in area is 



* "Bees and Bee-keeping," Vol. II., page 213. 



