INSTINCT OF INSECTS, 491 
opposite fourth cell. Lastly, we find cells in pretty con- 
siderable number, of which the bottom is composed of 
four pieces perfectly regular—namely, two elongated 
hexagons and two equal rhombs, but smaller than those 
of the pyramidal bottoms. In proportion as we remove 
our view from the cells with regular tetrahedral bottoms, 
whether in descending or from right to left, we see that 
the subsequent cells resume their ordinary form; that is 
to say, that one of their rhombs is gradually lessened 
until it finally disappears entirely; and the pyramidal 
form re-exhibits itself, but on a larger scale than in the 
cells at the top of the comb. This regularity is main- 
tained in a great number of ranges, namely, those con- 
sisting of male cells; afterwards the cells diminish in size, 
and we again remark the tetrahedral bottoms just de- 
scribed, until the cells have once more resumed the pro- 
per diameter of those of workers. 
It is, then, by encroaching in a small degree upon 
the cells of the other face of the comb, that bees at length 
succeed in giving greater dimensions to their cells; and 
the graduation of the transition cells being reciprocal on 
the two faces of the comb, it follows that on both sides 
each hexagonal contour corresponds with four cells.— 
When the bees have arrived at any degree of this mode 
of operating, they can stop there and continue to employ 
it in several consecutive ranges of cells: but it is to the 
intermediate degree that they appear to confine them- 
selves for the longest period, and we then find a great 
number of cells of which the bottoms of four pieces are 
perfectly regular. They might, then, construct the whole 
comb on this plan, if their object were not to revert to 
