Download Freaks and marvels of plant life; or, Curiosities of vegetation PDF

TitleFreaks and marvels of plant life; or, Curiosities of vegetation
TagsEucalyptus Trees Plants
File Size15.8 MB
Total Pages488
Document Text Contents
Page 1

Freaks and Marvels

OF Plant Life

^'L '^''lA^'4'

Page 244


facts themselves are placed on record, and hereafter

the key to the mystery may perhaps be found.
Spontaneous movements are common in the organs

of reproduction, being more or less associated with

the process of fertilization. " In Stylidium, an Aus-

tralian genus, the style and filaments are adherent

into a column, which hangs over on side of the flower.

When touched it rises up and springs over to the
opposite side, at the same time opening its anthers

and scattering the pollen. The stamens of the various

species of berberry {Bcrberis and JMalioiiid) exhibit

this irritability to a remarkable degree. If touched

with a pin or other object at the base of the inside

face of the filament, the stamen will spring violently

forward from its place within the petal, so as to bring

the anther into contact with the stigma, and will,

after a time, slowly resume its original position. At
first sight it may seem as if this contrivance were
intended to ensure the fertilization of the pistil from

the pollen of its own flower. In reality, however, the
reverse is the case ; the excitation takes place in

nature when an insect entering the flower for the

sake of the honey in the glands at the base of the

pistil touches the inside of one of the stamens. The
pollen is thus thrown on to the head or body of the

insect, which carries it away to the next flower it

visits, and leaves .some of it on the stigma, and thus

cross-fertilization instead of self-fertilization is secured.

Page 245


Similar motion of the

stamens towards the

pistil, but spontaneous,

takes place in the Lon-

don Pride and other

species of Saxifraga."-

This may be studied
also in that pretty

marsh-flower, the grass

of Parnassus {Par-

nassia palustris). In

this flower each of the

white petals has a

glandular appendage

at the base which

forms a portion of the

disc. It consists of a

crescent-shaped scale,

bearing on its margin

from sixteen to twenty

slender hair-like pedi-

cels, each of which

supports a globose

vesicle filled with fluid-

In the centre of the

flower is a rather largfe
Fig. 36. —Grass of Parnassus

[Partiassia palustris).

^ A. \V. Bennett, in " Popular Science Review," vol. xi.

(1872), p. 378.

Similer Documents