478 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
[ December 3,1891, 
The typical forms of Dodecatheon are all natives of North America ; 
some of the varietal forms of D. Meadia may have originated in our 
gardens, or have been introduced as natural varieties, since, like almost 
all the genera of Primulaceae, they are easily worked upon either by 
artificial or insect agency. They are all perennials, easily increased by 
division of the rootstock or from seed, although the seed if sown in 
spring i 3 frequently slow in germinating—in fact we have had it 
germinate after being in the pots twelve months. The seed should be 
sown as soon as ripe, but if purchased from a seedsman it is as well not 
to discard it until all probability of its germination is past. 
The plants produce erect racemose spikes of pendulous Cyclamen¬ 
like flowers during the early summer months, with the segments of the 
corolla sharply reflexed. The generic name assigned to these plants by 
Linnaeus is very absurd, as it literally means “ twelve divinities,” and 
like a multitude of other names the similarity or associations of the 
subjects in question with those represented only rests in a very remote 
region of the imagination. Below are enumerated some attractive 
species and varieties. 
Dodecatheon integrifolium is widely distributed over North 
America, varying to some extent; it grows from 9 to 12 inches high, 
producing numerous spikes of bright crimson flowers, which last a con¬ 
siderable time in beauty. This is as handsome and durable as any of 
them. 
D. Jeffreyanum is a more recent introduction than the last; it varies 
in height from 1 to 2 feet, usually growing about 18 inches high, pro¬ 
ducing strong scapes of bright rosy purple flowers, which are also 
rather larger than those of the last. 
D. Meadia is the most common of the series, and is frequently known 
as the “ Shooting Star of the West.” It is very widely distributed 
throughout North America, and there is a large amount of variation, 
■which has originated the establishment of many varietal forms. The 
typical form produces scapes about a foot high, bearing several flowers 
of lilac or rosy red colour. It is a very valuable species, and will thrive 
well in ordinary borders if a select position is given to it and a little 
attention. For growing in pots it is valuable, and the cultivator is 
well rewarded. 
Varieties of this species worth growing are album, which is similar 
in all respects to the type, but has white flowers. Elegans, a charming 
variety ; the flower scapes are freely produced, bearing several large, 
bright rosy lilac flowers. This is also a vigorous grower. Carneum, 
with very delicate blush flowers, produced in very large umbels. 
Giganteum, a tall-growing variety 18 inches high ; the umbels large, 
bearing dark rose-coloured flowers. The American Cowslips represented 
in the illustration (fig. 88) were grown by Mr. Ware at Tottenham. 
INSECTIVOROUS PLANTS. 
Before a large audience at the weekly meeting of the Richmond 
Athenaeum in the College Hall last week, the Rev. Professor Henslow, 
M.A., F.L.S., delivered a lecture on “Insectivorous Plants.” The Rev. 
Astlev Cooper presided. The Lecturer said that the subject was of 
extreme interest, and as in many similar cases they were indebted to 
Mr. Charles Darwin for a large amount of information on the 
subject. Very little had been added to the information given in his 
book on “ Insectivorous Plants,” and those who desired further in¬ 
formation on the subject he referred to that book. In former days it 
was supposed to be the great distinction between animals and plants, 
that plants lived upon the mineral kingdom and animals lived upon 
the vegetable. A very large number of plants lived upon the mineral 
kingdom, water, gases, and things dissolved, but many can also catch 
flies and insects, and sometimes seeds which happen to drop upon them, 
and devour them. This opened our eyes to the fact that the process by 
which they do it must be very much like what animals and we ourselves 
do. The insectivorous plants were found in all parts of the vegetable 
kingdom. Botanists divided up plants into families, and considered all 
plants in one family to have a certain amount of affinity. They 
believed that they all came down from some ancestral form and were 
related. But the insectivorous plants were scattered all over the vege¬ 
table kingdom, and had no other affinity at all. The process by which 
they secured their prey was sometimes something like a rat-trap, some¬ 
times a tube into which insects crawled and could not get out, some¬ 
times a little box with a kind of lid, while others secreted a gummy 
fluid. These methods were found scattered about through the different 
families, one family adopting one method, one another, and sometimes 
it was found that a method adopted in one family reappeared in another. 
That opened out the question how had all these things arisen ? The 
general idea was that this power had arrived somehow or other to be 
the common property of ail plants of the vegetable kingdom ; that there 
was in every plant a living matter called a protoplasm, which had the 
power of acquiring carnivorous habits under certain conditions. This 
would show that there was unanimity running through the whole of 
the vegetable kingdom. Most of the insectivorous plants were thousands 
of times larger than their prey, but there was a large number of in¬ 
sectivorous plants which were much smaller than their prey. In that 
case they ate them in a different way, and these were called parasites. 
The little “ Sundew,” which would be found growing on Hampstead 
Heath, was an insectivorous plant. It was found in boggy places, grow¬ 
ing amongst the bog moss, where it was very wet, and had scarcely any 
roots. It produced round leaves upon long stalks, and ultimately 
flowers. On a bright sunny day the leaf, which is green, is covered all 
over with what looks like very stout hairs. Mr. Darwin suggested the 
term tentacles, as they were not strictly the same as hairs upon plants. 
Every one of them terminated with a globular head, which secreted 
gum. This glistened in the sun, and they thus got the name of Sundew. 
That was its condition when it was ready to catch flies. It was un¬ 
known what attracted insects, but insects were constantly found on 
them. If a person took a minute fragment of hard-boiled egg or little 
bit of meat and laid it on the top of one of these long tentacles, the 
food immediately sank through the gum and reached the gland, as 
botanists called it, and in a very short time a curious phenomenon 
took place. The tentacle began to secrete, the gummy fluid became 
acid, and the tentacle began to bend in slightly towards the middle, 
carrying the pat tide of food which had been placed upon it into the 
centre of the leaf. The glands instantly began to pour out the acid 
as well, and what was still more remarkable, though none of the. other 
tentacles had been touched, they all knew that there was something to 
eat in the middle of the leaf, and would slowly bend over until every 
one of them had placed its gland upon the bit of meat that had been 
put there. All began to pour out this acid, and they did it before they 
touched the meat—their mouths began to water, to use a metaphorical 
expression. It was a kind of reflex action caused by the irritation set 
up. The same effect was caused, said the Professor, when a human 
being began to eat anything. After everything had been digested which 
the plant could digest the plant resumed its normal habit, what re¬ 
mained of the fly, or whatever it was, is thrown off, and the leaf is 
ready for another prey. It had been asked what was the use of this 
food'/ could not the animal live without it 1 Dr. Francis Darwin, with 
a view to testing this, experimented with two lots of insectivorous water 
plants. One lot he fed regularly, and the other lot he gave nothing to 
but the water they grew in. The plants that were fed looked much 
better than the others. The weight of their seed was as 157 to 100, the 
number of their seed was as 111 to 100, and the number of capsules 
produced was as 191 to 100. This showed that the great effect lay in 
the reproductive process. Parasitic plants, such as Broom Rapes, 
Dodders, and others lived on their hosts, and while they never made any 
green leaves always abounded in an enormous quantity of seeds. The 
benefit in the fed plants was in the reproductive process, the foliage part 
became terribly degraded and vanished altogether. 
A curious thing was that what was indigestible to a human being 
had the same effect on a plant. If a piece of cheese was put on the 
leaf the plant would pour out an enormous quantity of acid in order to 
manage it. It was the same with them. They took cheese as a rule 
after dinner, when the fluid secreted to digest the cheese attacked the 
other food and left the cheese undigested. He next dealt with a plant 
which was found abroad called “ Venus’s Fly-trap.” Each leaf was 
fitted with a kind of winged stalk. There were prominent bristles on 
the inner face of each half of the blade. On the slightest touch the 
blades collapsed and went together like a rat trap. They did not at 
first close very tight, and a small insect might escape; but if a blue¬ 
bottle got in the more it struggled the tighter the blades closed, and it 
could not possibly get out. This action bore some analogy to the action 
of a human muscle. Having described the action of the Sensitive Plant 
when touched he passed on to a little plant which lived much in water— 
the Aldrovanda. It had a large quantity of bristles all over the middle, 
covered with glands, and groups of four cells. If the plant had got any 
little water prey the glands secreted. Then there was a little water 
plant generally found in muddy ditches. It had little black knobs that 
were once supposed to be floats, but were now known to be traps for 
catching insects. The little hollow bladders with hairs protruding 
made something of a hollow cone. When insects got into the hole 
it was impossible for them to get out again, as there was a flap 
which covered the hole, which they could not lift up. That plant had 
got no glands with which to secrete the digestive fluid, but instead was 
covered all over on the inside with quadrafid process. Nothing it was 
now known could decay without the bacillus or microbe to do the -work. 
Those microbes, of which we heard so much, set up a ferment. Thunder 
weather was a very favourable condition for the aggregation of microbes, 
and thus it was that the milk went sour so much more quickly. Of 
those insectivorous plants some required microbes to bring out putrefac¬ 
tion in the animal, and those quadrafid processes absorbed the decayed 
food. Another plant was one called the Bladder-wort, and another the 
Butter-wort. They were found abundantly in the west of England and 
ia Wales. The leaves were covered all over with glands, and the glands 
looked like complicated buttons under a microscope. Their cells 
radiated from a centre, snd the crimped-in edge3 stood on a little 
pedestal or stalk. If a fly or anything else fell upon it the margin of 
the leaf began to roll over, and enclosed the insect. 
The fermenting glands were the next things in plants. Very often 
they secreted oils, as in Lavender, and they were believed by botanists 
in other plants to be the means of casting off excretions which the plant 
did not require. There was a foreign tree called the Papaw, and it was 
a common habit to take the leaves of this tree in which to wrap tough 
meat. The plant had a power of secreting a nitrogenous ferment, which, 
