POLYPHYLLY. 359 
other perceptible change, while at other times the 
number of the other parts of the flower is proportion- 
ately increased. In a flower of a plum six sepals in 
place of five sometimes exist; a precisely similar 
occurrence in the flowers of the elder (Sambucus), the 
Fuchsia, and of Gnanthe crocata, may occasionally be 
met with. In the latter case, indeed, there are some- 
times as many as ten segments to the calyx, and 
this without the other parts of the flower being 
correspondingly augmented. Among monocotyledons 
a similar increase is not uncommon, as in Tulipa, 
Allium, Iris, Narcissus, &c. 
In some plants there seems to exist normally much 
variation in the number of parts; thus in some species 
of Lacistema im adjacent flowers the calyx may be 
found with four, five, or six segments. 
Most of these cases of polyphylly affecting the calyx 
may be explained by lateral chorisis or fission. 
Polyphylly of the corolla—This may happen in connec- 
tion with similar alterations in the calyx and stamens, 
or sometimes as an isolated occurrence. In the latter 
case it may be due to lateral chorisis, to substitution, 
or to the development of organs usually suppressed ; 
thus, when in aconites we meet with four or five horn- 
like nectaries (petals) instead of two only, as usual, the 
supernumerary ones are accounted for by the inordinate 
development of parts which ordinarily are in an abortive 
or rudimentary state only. This is borne out by what 
happens in Balsaminee. Inthe common garden balsam 
the fifth petal is occasionally present, while in Hydrocera 
trijlora this petal is always present. 
In a flower of a Cyclamen recently examined there 
were ten petals in one series, the additional five bemge 
evidently due to the subdivision of the five primary 
ones; the natural circular plan of the flower was here 
replaced by an elliptical one. A similar occurrence 
takes place in the flowers of maples (Acer), which 
sometimes show an increased number of parts in their 
