ARTIFICIAL AIDS TO COMB-BUILDING, 
221 
distinct cells in B. The lower rhombs in the line 
a b' belong to the attachment cells in B, while their 
opposite sides {a b) form the upper rhombs of the 
second row of cells of A ; these cells, and those of 
every other row, having their rhombs arranged as those 
of B inverted — i.e., the anterior face of a piece of founda- 
tion becomes the posterior one by simple inversion : 
so that foundation, although having sides, as we have 
already seen, has, strictly speaking, neither top nor 
bottom ; or, with regard to it, these terms are con- 
vertible. The variation in the height of corresponding 
I 2 3 4 5 6 ^5 6' 5' 4' 5' 2 \ 
A, Posterior Face. B, Anterior Face. Similar letters and figures refer to opposite 
sides of the same parts in each. 
rows of cells on the two faces, is indicated by the 
similarly lettered lines in the Figure, and, while it is 
clear that the attachment cells of the posterior face (A) 
must be sufficiently deep to admit a bee, those on 
the anterior face must be deeper by half the diameter 
of the ordinary cells, measured between the angular 
points instead of the parallel sides ; i.e., they must 
be far too deep and irregular in form, both in the 
sides and bases, to be suitable to breeding purposes — 
a point the import of which we shall presently see. 
