tances, the sepals may be considered as the
representatives of the sheath of the leaf (cataphyllary) or of the blade
(euphyllary), the arrangement of the veins being different in the two
cases; thus, in the vagina or sheath, there are generally several large
veins of about equal size, either convergent towards the apex, or
divergent; on the other hand, in the blade, there is usually but one
central vein, the midrib, larger than the rest, and the smaller veins
come off at a less acute angle, and are more reticulated.[257]

Now, when phyllomorphy occurs in sepals which ordinarily are vaginal, it
is obvious that the case is one, not merely of increased relative
growth, but also of the appearance or development of an organ habitually
suppressed; on the other hand, when phyllomorphy occurs in sepals which
usually are laminar in form and nervation, the case is one of unusual
growth or hypertrophy, and not of the development of an organ habitually
suppressed, so that the amount of change is greater in the former than
in the latter instance.

Under normal circumstances it will be found that laminar venation is
most common in gamosepalous and vaginal venation in polysepalous
calyces. And the same holds good in cases where the calyx is abnormally
leafy. The complete leaf development shows itself more frequently among
the monosepalous plants than in the polysepalous ones, as shown even in
the subjoined list of species. This statement would be more fully
verified were it possible to state the frequency with which the
condition occurred in _individual plants_, when it would be found that
phyllody of the calyx occurs much more often in individual gamosepalous
plants than in polysepalous ones.

Phyllody of the calyx has been most often observed in the following
plants:

Ranunculus acris!
Delphinium Ajacis.
Caltha palustris.
Anemone Pulsatilla.
sylvestris!
nemorosa!
hortensis!
coronaria!
*Papaver orientale.
Escholtzia crocea.
Cakile maritima.
Diplotaxis tenuifolia.
Thlaspi arvense.
Cheiranthus Cheiri.
incanus.
Sinapis arvensis.
Brassica oleracea!
Peltaria alliacea.
*Sisymbrium officinale.
Caryophyllaceae,[258] sp. pl.
Geranium, sp.!
*Fuchsia, var. hort.!
Epilobium hirsutum!
Cucurbita Pepo!
*Rosa, var. hort.!
Potentilla nepalensis.
Fragaria sp.
Geum rivale.
Amygdalus communis.
Persica vulgaris.
Cerasus!
Py