526 
MORPHOLOGY 
BOOK VI. 
down to the sixth generation." The substance of the subse- 
quent observations is this. 
" If a plant, which has flowered and fruited for many suc- 
cessive years in a pot, is transferred to a rich soil and warmer 
station, it breaks forth into branches instead of flowers. 
Hence it appears that branches and leaves can be produced 
from the provision made for flowers, provided circumstances 
are favourable to their developement." 
As to bracts, " the bulbs of hyacinths and ornithogalums 
afford good evidence of their nature. Both bulbs and buds 
are winter coverings of plants, with this difference, that bulbs 
are the bases of leaves of the previous year, while buds are 
the rudiments of leaves of a coming year. Wherever bulbs 
grow, there are formed the persistent bases of leaves, within 
which young leaves are to be developed : within these latter 
leaves repose the buds or rudiments of future plants, exactly 
the same as the buds of trees. These buds consist of the ru- 
diments of leaves of the succeeding year ; small indeed, but 
containing in their axils other rudiments of like nature. 
Now, if it happens that such a plant flowers, the bud, which 
would otherwise have produced leaves the year after, is con- 
verted into a scape a year earlier ; whence it comes to pass 
that the rudimentary leaves lying in the bud lose a part of 
their nutriment, in consequence of the sap being drawn off to 
the fructification : wherefore those leaves continue small, 
assume a diff*erent structure, easily wither, and are called 
by botanists bracts. Thus bracts are nothing but leaves 
which would have been developed another year if the plant 
had not flowered." 
As to the calyx. " That the calyx is only the approxi- 
mated leaves of a plant, is apparent from several instances. 
The calyxes of Pyrus and Mespilus are often expanded into 
perfect leaves ; the rose offers a similar instance of the change. 
The leaves of Mesembryanthemum barbatum are supplied 
with a most curious apparatus of hairs ; and the calyx con- 
sists of five pieces, in all respects similar to the leaves of the 
stem. The calycine leaves, indeed, are often very small, 
juiceless, and different from those of the stem, as if scales of 
buds previous to their developement ; but that they still are 
