racts of the involucre and the scales of the receptacle had all assumed
the form, texture, and venation of leaves.[247]

[Illustration: FIG. 127.--Leaf-like bracts in _Plantago major_.]

[Illustration: FIG. 128.--Dahlia. Scales of receptacle leafy.]

In _Umbelliferae_ the substitution of leaves for involucral bracts is not
infrequent. It has been observed among other plants in _Angelica
Razoulzii_, _Carum carui_, _Daucus Carota_, &c. The scales of the hop
(_Humulus Lupulus_) not infrequently manifest this change, as do also
the bracts of many amentaceous plants, _e.g._ in the male catkins of
the walnut, the female catkins of the alder,[248] of some willows,[249]
&c. The bracts of some _Euphorbiaceae_, as _E. pusilla_, _E. Lathyris_,
_E. Cyparissias_, have been observed to undergo a similar
alteration.[250]

Amongst monocotyledons an analogous change occurs not unfrequently, as
in some commelynaceous plants, _e.g._ _Tradescantia_, in _Musa_, &c.

The spathe of _Arum maculatum_ is sometimes represented by a stalked
leaf similar to that which occurs, under ordinary circumstances, in
_Spathiphyllum_, but in which genus the spadix is more or less adherent
to the leaf-like spathe.[251] In _Schoenus cephalotes_ a similar
exaggerated development of the bracts is figured by Rottboell.[252]

=Phyllody in inflorescence of Conifers.=--This demands passing notice by
reason of the interest attaching to the morphological construction of
these plants. The elongation of the axis which occurs in the female
cones has been already alluded to under the head of prolification of the
inflorescence. This change is frequently associated with a more or less
foliaceous condition of the bracts, which, indeed, may be seen to be
serially continuous, both above and below, with the ordinary leaves. The
scales, too, become notched and bipartite, and show, between the lobes,
the rudiment of a bud, which in a further stage becomes developed into a
shoot bearing leaves. Such a change has been described by Parlatore in
_Abies Brunoniana_, and examples may frequently be met with in the larch
(_Larix europaea_), and specially in _Cryptomeria japonica_.[253] The
scales of the male catkins of conifers likewise occasionally assume the
appearance of leaves; this may be seen in monstrous catkins of
_Araucaria_, as also in _Podocarpeae_ and _Cupressineae_ (Eichler).

=Phyllody of the calyx.=--Sepals under ordinary circumstances are so
like leaves, that it is