ke anther of _Jatropha_ described by M. Mueller,
p. 255.

=Cornute leaves= (_Folia cornuta_).--The condition to which this term
applies is that in which the midrib, after running for a certain
distance, generally nearly to the point of the leaf, suddenly projects,
often in a plane different from that of the leaf, and thus forms a small
spine-like out-growth. Should this happen to be terminated by a second
laminar portion, an interrupted leaf would be formed. In _Scolopendrium
vulgare_ and other ferns this condition has been noticed, as also in
some of the varieties of _Codiaeum variegatum_ already referred to.

=Flattening.=--There are some plants whose stem or branches, instead of
assuming the ordinary cylindrical form, are compressed or flattened;
such are some species of _Epiphyllum_, _Coccoloba_, _Bauhinia_, &c. The
same thing occurs in the leaf-like branches of _Ruscus_, the
flower-stalks of _Xylophylla_, _Phyllanthus_, _Pterisanthes_. Martins
proposes to apply the word 'cladodium' to such expansions, just as the
term phyllodium is applied to the similar dilatation of the leaf-stalks.
If we exclude instances of fasciation, _i.e._ where several branches
are fused together and flattened, we must admit that this flattening
does not occur very often as a teratological appearance.

Mr. Rennie figures and describes a root of a tree which had become
greatly flattened in its passage between the stones at the bottom of a
stream, and had become, as it were, moulded to the stones with which it
came into contact.[364]

The spadix of _Arum_, as also of the cocoa-nut palm, has been observed
flattened out, apparently without increase in the number of organs.

When the blade of the leaf is suppressed it often happens that the stalk
of the leaf is flattened, as it were, by compensation, and the petiole
has then much the appearance of a flat ribbon (phyllode). This happens
constantly in certain species of _Acacia_, _Oxalis_, &c., and has been
attributed, but doubtless erroneously, to the fusion of the leaflets in
an early state of development and in the position of rest.[365]

In some water plants, as _Sagittaria_, _Alisma_, _Potamogeton_, &c., the
leaf-stalks are apt to get flattened out into ribbon-like bodies; and
Olivier has figured and described a _Cyclamen_, called by him _C.
linearifolium_, in which, owing to the suppression of the lamina, the
petiole had become dilated into a ribbon-like expansion--deformation
rubanee