M 
3(53 
rivale, where the sepals are usually large and leaf-like, as they likewise are frequently in 
proliferous Roses and Pears. 
Proliferous Roses have a special interest, inasmuch as they show very conclusively thai 
the so-called calyx tube of these plants is merely a concave and inverted thalamus which, 
in prolified specimens, becomes elongated after the fashion of Geum rirole*, etc. I have 
in my possession a Rose, wherein from the middle of the outer surface of the urn-shaped 
thalamus proceeds a perfect leaf, which could hardly be produced from the united sepals 
or calyx-tube; a similar occurrence in a Pear is figured in one of the plates of Keith's 
1 Physiological Botany', sketch 4. 
An important change in the calyx necessarily occurs when flowers with an habitually 
adherent ovary become prolified, as the calyx is then disjoined from the ovary ; its con- 
stituent sepals are then frequently separated one from the other, and not rarely assume 
more or less of the appearance of leaves, as in proliferous flowers of Umbel 7 if, rat, Cm* 
panulacece, Composites ', etc 
i 
As to the corolla, it was long since noticed that prolification was especially liable to occi 
in double flowers; indeed Dr. Hill, who published a treatise on this subject, getting fort 
the method of artificially producing prolified flowers, deemed the doubling as an almost 
necessary precursor of prolification t ; but, though frequently so, it is not invariably the 
case that the flower so affected is double-*, g. Geum, If double, the doubling may arise 
from actual multiplication of the petals, or from the substitution of petals for stamens 
and pistils, according to the kind of flower affected. Occasionally in prolified flowers, the 
parts of the corolla, like those of the calyx, become foliaceous, and in the case of proli- 
ferous Pears fleshy and succulent. There is in cultivation a kind of Cheiranihmfm 
which there is a constant repetition of the calyx and corolla, conjoined with an entire 
absence of the stamens and pistils ; a short internode separates each flower from the one 
above it, and thus frequently ten or a dozen of these imperfect flowers may be seen on 
the end of a flower-stalk, giving an appearance as if they were strung like beads, at 
r 
intervals, on a common stalk. I have seen a similar instance in a less degr 
a species of Heliantliemum . . . 
The stamens are subject to various changes in proved flowers; they assume, for in- 
stance, a leaf-like or petal-like condition, or take on them more or less of a carpellary form, 
or they may be entirely absent ; but none of these changes seem to be at all n. cessanty 
connected with the proliferous state of the flower. Of more interest is the change m „ 
position of these organs which sometimes necessarily accrues from the elongation of the 
axis and the disjunction of the calyx : thus in proliferous Eoses the stamens become stnetly 
hypogynous, instead of remaining perigynous. In VMUferce the epigynous oond..t. on 
is changed for the perigynous, etc. m ' i ,. 
The condition of the pistillary organs in a prolified flower ts always <"£*«-*" 
The freouent complete absence of the carpels gave rise to *e opunon £ b pstdor 
the pistils were converted into a stem bearing leaves or flo* eis. &etun a i 
Bell Salter, Ann. Nat. Hist. 1847, vol. xix. p. 471, etc. R from 
t ■ The Origin and Production of Proliferous Flowers, with the Culture at large tor raismg u 
Single, and Proliferous from the Double." By J. Hill, M.D. London, 1 7o9. 
