So 
THF TROPICA!. AGRICULTURIST, 
[July i, 1891 
vertically they would see packed away in the centre 
the young plant which was to sprout in the year 
following. Sometimes this stowing aw'ay of vegetable 
starch underground would ii© utilized for purposes 
of propagation. Kvorybody was acquainted with the 
fact that the potato had Ho>called eyes, from every 
one of which potato plants would sprout, and they 
could cut up tne vegetable with impunity as long as 
they did not injure this eye. This w’as the case also 
with the tubers of the artichokes. Even as regards 
the leaves, said the lecturer, which were to be 
brouglit forth next siunmer, they were already 
formed. If we looked upon any lilac bush, or horse- 
cliesnut tree, or, indeed any shrub, we should find 
them crowded with brown buds. If these wore cut 
in halves the leaves w’ould be found packed away 
within the protective bracts, which were really modi- 
fied leaves, which never Ijecauto leaves, but which 
sacrificed themaclves, for the sake of the tender little 
leaves which they cnclosetl, l^ven the flowers Dr. 
Taylor said, in some instances, tliat were to come 
next year, had been provided for last season, as in 
the case of the catkins of the hazel which were now 
shedding their pollen from the hedges by the wayside. 
In all these cases the lecturer pointed out that one 
of the most important elements, Nitrogen, which en- 
tered into the composition of plant food, and whicli 
article we supplied to crops in nitrate of soda, was 
taken by the root hair of the plants from the soil. 
We were surrounded in the atmospliere iiy a huge 
reservoir of nitrogen, composing 79 per cent of the 
constituents of tlie atmosphere. No order of plants 
however except the podded plants like beans or peas, 
had the power of tapping this vast aerial supply. 
But supposing, said the Curator, that plants were 
80 situated that these roots could not penetrate 
the soil to obtain any of the nitrogenous 
materials which the soil contained. The only means 
by which the soil was refreshed was by tlie dead 
bodies of animals, botJi great and small. Mother 
Earth had been for millions of years receiving back 
to her bosom the children to which slie had given 
birth, microscopically Bmall, and gigantically large. 
Sometimes, of course, the soil was refreshed from 
tlie atmosphere, as during thunderstorms, when the 
lightning uash had the power of combining in its 
path the nitrogen with the oxygen, and producing 
tliereby fertilising nitrous oxide. The soil contained 
Iiosts of bacteria, wliioh were engaged in the work 
of converting decomposing matter which contained 
nitrogen, so that it should be soluble for the root 
hairs of plants; nitrifying the soil, in short. Now, 
he said, there were groups of plant.s whose nature 
had been only studied during the last twenty years, 
which now went by the name of carnivorous or in- 
sectivorous. Most of them lived in marshy spots in 
various parts of the world. These plants, as a rule, 
had roots which were simply so many anchoring 
threads, to prevent the plant oeing blown away. So 
the duty of obtaining nitrogen was thrown upon the 
leaves, and these loaves, in tlio process of the battle 
of vegetable life, and the keen strife that liad been 
going on for ages past in the vegetable kingdom, de- 
veloped special powers of capturing animals— that is 
to say, insects of all kinds, small fish, and oven birds. 
The lecturer rofored to, first, the sundew, of which 
wo have throe species in England. This plant was 
found in both North and South America, the Cape of 
Good Hope, and other places, but it was most prolific 
in Australia, where there were no less than forty 
kinds. All of them possess the power of capturing, 
strangling, and oven digesting insects which visited 
them. By moans of diagrams ho pointed out the 
structure of these curious plants, showing how a 
rosette of green leaves, which were crowded with 
tentacles, that were really only portion.s of leaves 
extended like the fingers of a glove, secreted dow- 
liko drops, and the greater the sunshine the greater 
the quantity of this glutinous material. Tiiey w'ere 
exceedingly sensitive to anything touching them of 
a nitrogenous nature. One eighty-thousandth part 
of a gram of ammonia affected them. The tentacles 
would then flex themselves over and show that they 
were influenced. Microscopic examination showed 
the protoplftsinio stream in agitation under nitro- 
genous stimulancy. Insects, in proportion to their 
size, contained more nitrogen than any other kind of 
creature. Along our hillsides sometimes tliey would 
HOC in the boggy districts a large area of the country 
crowded with sundews, the most remarkable plant of 
our J^ritish flora, and insects would be attracted by 
the sparkling dew’ to have a drink. Mlien they alighted 
upon tlto leaf the hapless creature W'oula be 
entangled among the glutinous, viscid matter, so as to 
bo unable to get away. Then the tentacles would 
flex themsolves over it, the edges of the loaf would 
curl up, the insect would be strangled and suffocated. 
Decomposition w’ould set in, and the leaves actually 
oHsosB the fluid pepsino like the human stomach, 
y which it could digest the nitrogen and assimilate 
it. Then the tentacles would turn to their old position, 
and the empty case of the insect would bo blown or 
washed away. The Doctor then related various ex- 
periments wiiicli he hod made on these carnivorous 
plants. Another plant growing on our hillsides w'as 
the butterwort, so called from its rosette of greasy 
leaves. There were certain kinds of insects called 
plant lice, which when they attacked the leaves of 
this butterwort slipped about its surface like a l.anky, 
bad skater. These plants had also the function for 
digesting those insects which the loaves had captured, 
lie next described an aquatic carnivorous plant 
which was to he found in the River Gipping, and 
they might often liave seen its yellow spikes just 
appearing above tlie water level. Tlioy were regular 
eel traps as regarded their structure; minute water 
flies or the larvffi of flsh could get in but they could 
not get out. They wore strangled and digested, 
'riie Doctor then referred to the great pitcher plants 
of the Malay Archipelago, so huge that sometimes 
they held half a gallon of water, in shape they 
W’ere like a liot-w'ator jug with the cover half lifted. 
Bmall birds frequented them to drink, but having 
partaken, wlion tliey strive to get out they are 
driven back by two Itu'ge pointed spikes, until at 
length they are drowned, in the liquid there were 
actually bacteria present, which lielped to decompose 
the birds, and in this way the uepenthus plant 
jirovided itself witli nitrogen. In North America 
tliero was tlie side-saddle plant, the sarnacenin and 
darliiigtonia, which also caught flies on their pecu- 
liar iind suggestive manner, so that the interiors 
of their trumpet-shaped entrances w’ore frequently 
crowded with flies, dead and dying. Bingularly 
enougli these plants not only had a bright attractive 
colour at tlie upper part of the trumpet-shaped tube, 
but they also secreted lioney, and a fly lighting 
upon it might imagine that it was quite safe to 
sip. It got sweeter lower down. The interior, 
liow’ever, was covered with hairs, w'hich grow down- 
wards, and when the insect tried to come back it 
dropped to the bottom, to join its foolish brethren 
who had come the same way. They were decom- 
posed witliin, and tlius the side-saddle plants of 
America, through their modified leaves as pitchers 
and trumpet-like tubes, fed themselves in this remark, 
able manner. 
THE DEFENCES OF PLANTS. 
The immediate subjects of the lecture were in 
touch w'ith those treated on in previous discourses 
altliougii of a distinctly individual character. Dr 
iaylor brought before his hearers n the first instance 
the subject of the defence of plants. From what he 
had said concerning the usefulness of greon loaves 
it would be seen that tlio loss of a single leaf was 
decidedly injurious to the plant. Jle asked thciii 
to consider the vast number of enemies wliich plants 
had to cope w’itli. for it might be said that the whole 
animal kingdom depended for its existence 
upon tlio vegetable. Not only did mammalia browse 
upon herbaceous plants, but tho iarvm of untold 
millions of insects did so too. In addition to these 
were the slugs, snails, (fee., which fed ojitiroly upon 
vogetablo structures. Perhaps numerous spare leaves 
on every tree wore provided for the sole purpose of 
meeting the demands of tlie animal kingdom. It is 
no uncommon thing during a droughty sunimep, 
to see the ground and the hedge rows stripped of 
tlveir leaves entirely through the depredatiens of 
