TlIK .M(>V1:.MI:NIS oI' I'LANI' oliCANS. 
1)9 
Darwin has described nuinerous instances of movements in the 
flowers of Orchids, in wliich the poUinia, as of the common Orchis 
masciila and others, or of Catasction, Sec, have remarkable powers of 
movement- in the former case, slow, but in the latter rapid.* 
Stj/lidiunt aftbrds another illustration of rapid motion. In this flower 
the stamens and style are consolidated into a column, which is curiously 
bent and hangs over one side of the flower. If it be touched near the 
base it instantly flies over to the other side. A very similar movement 
occurs in the pistil of Maranta. 
Some ilowers have the stamens in a certain position on first expanding, 
bat they take up a dififerent one subsequently. This is not infrequent, as in 
May, Water-plantain, &c., in which the stamens are spread out at first, 
but subsequently curl inwards upon the pistil, apparently to secure self- 
fertilisation if the flower has not been crossed. 
In several flowers of plants of quite different orders the filaments retire 
after the anthers have shed their pollen to make room for the style and 
stigma, which are later in developing, and then stand where the stamens 
were before. This occurs in the lemon-scented Pelargonia, in Teucrium 
Scorodonia, our Wood Sage, and many other plants. 
All the above described movements are s'ital, in that they are con- 
nected with the living protoplasm which executes them. They must, 
therefore, be distinguished from purely mechanical movements of bursting 
of seed-vessels, the uncoiling with a spiral movement of awns of Grasses 
and of Erodium, which are due to moisture. 
* Fertilisation of Orchids. 
