370 AMERICAN HOMES “AND "“GARDERes 
take the trouble to look 
about them when they wan- 
der in rural districts, may 
verify most of the points 
raised. Let us begin with 
the food of plants. ‘This, in 
the main, is carbon, which 
they extract from the 
minute particles of carbonic 
acid which float in the air 
around them. Also, as 
every one knows, plants re- 
quire much water for their 
well-being. But in addition 
to carbon and water, plants 
also need small quantities of 
certain other chemical sub- 
stances; and these they take 
up in solution by means of 
their roots. Most important 
A Nepenthes pitcher 
How the Virginia creeper takes hold 
September, 1909 
held fast in just the same 
way as they would be by 
the gum of an ordinary fly- 
paper. Then the leaf be- 
gins slowly to bend over 
and clutch its victim, pour- 
ing a peptic secretion upon 
it by means of the red hairs, 
and ultimately absorbing 
the juices of its decay. 
Now the reader may be 
inclined to regard this as a 
kind of mechanical action. 
But it has been shown by 
experiment that the sundew 
knows exactly what it 
wants, how to obtain this, 
and how to deal with it 
when secured. Mrs. Mary 
Trent observed closely the 
of these dissolved substances required by the living plant is common American sundew, and found that the leaves would 
nitrogen. ‘his brings us to an extremely interesting phase actually move away from the light toward insects which she 
of plant ingenuity. Nitrogen, which we had pinned in their vicinity—moving as 
have seen constitutes a small but essential much as an inch in order to grasp their 
part of the plant’s diet, may, for prac- prey. She found, too, that while the 
tical purposes, be regarded as what leaves curled over -and digested the 
farmer’s call manure. In other words, smaller insects which settled upon them, 
decaying animal substances of all kinds they discarded the bulky ones—allowing 
consist largely of nitrogenous substances. them to fall about the roots of the 
Most soils contain sufficient nitrogen to plants, thus providing for themselves a 
supply the needs of the plants which surface dressing of manure. Equally 
grow therein. But very wet and boggy wonderful and suggestive of intelligence 
soils are generally lacking in this neces- was the sundew’s power of discrimina- 
sary element, and the plants which man- tion. They would digest tiny morsels of 
age to grow in such spots flourish only steak, when given; but cinders, bits of 
because they have solved the problem moss or straw, or little pellets of paper, 
of obtaining nitrogen for themselves. In they would have nothing to do with. 
a word, they catch flies, kill them, and The leaves seemed to realize that these 
absorb their decaying juices. These objects were unfit for food, and refused 
clever plants, which procure their own to waste time and digestive fluid upon 
manure, set about the business in several them. | 
ways, all of which exhibit a marvelous ; Other plants, such as the Venus’s fly- 
ingenuity. The well-known sundews A Nepenthes plant with pitcher developed | trap of the South Carolina bogs, are still 
have leaves covered thickly with sticky on leaf tips more expert. The end of each leaf in 
red hairs. When a fly settles upon a the case of this species is arranged to 
leaf, to which it is probably attracted by the smell of the work after the manner of a gin. It is hinged in the middle, 
viscid secretion, its legs and wings are at once caught and_ and the edges are beset with stiff, incurved bristles. Upon 
The strength of a 
show mass of flies pitcher pitcher dead tendril 
A section of Nepenthes showing A pitcher slit open to A Sarracenias Flies and a 
partly digested flies 
