Jane 7,188S.] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
475 
them with roots before water was poured into the pots. They were well 
syringed, ami the plunging material kept moist. Lift two Hoses, pot 
them, and plunge one outside in ashes below the surface, and stand the 
other on the walk. Water one when it needs it, and give the other none, 
if the soil is in a proper state of moisture when potted. Examine 
when frost compels their removal to frames, and it will be found that 
the plunged one has double the roots of the other, and the soil in a much 
sweeter and better condition. Plunge Lilacs, Guelder Hoses, or any 
sirhilar plant after potting or pruning in autumn in ordinary garden 
soil for the next season’s forcing, and the season must prove exception¬ 
ally dry if they need a supply of water. 1 need not enumerate ex¬ 
amples of the advantages gained by plunging, becauss they can be 
tested by all who will put the system into practice. From a general 
system of plunging Orchids must, however, be e.xcepted, 
I said it was necessary to consider the disadvantages that could be 
urged against plunging. The only one of weight that can be brought 
forward is that of over-watering. Now, this when carefully considered 
is a difficulty that bears no comparison with the mistakes that are 
made, often unavoidably, in watering plants when their pots are ex¬ 
posed. Watering properly when the pots are plunged is a mere matter 
of training. If they are over-watered it arises from either lack of 
proper training, ignorance, or generally from carelessness. To water 
plants properly when they are plunged only needs observation and 
thought. This seeming difficulty in a method of procedure that offers 
advantages, the importance of which cannot well be over-estimated, is 
readily overcome. 
THE DISPEESION OF SEEDS AND PLANTS. 
It may seem strange, at first sight, to assert that cattle have been 
the means of distributing the seeds of certain plants from one country 
to another, but a statement is made by Grisebach respecting Pithecolo- 
bium Saman, a large tree native of Tropical America, now naturalised 
in Jamaica, that the “ seeds were formerly brought over from the Con¬ 
tinent [of America] by cattle.” This statement has been carefully 
examined, and it is fully borne out by facts. Formerly, Jamaica, like 
Trinidad at present, was dependent for cattle on Venezuela. The food 
of the animals during their voyage consisted amongst other things of 
the pulpy legumes of Pithecolobium Saman. The seeds being very hard 
were uninjured by the process of mastication and digestion, and they 
were deposited in the pastures, where they germinated and grew 
up into large trees. In this instance the seeds were carried across 
the sea a distance of about a thousand miles, and there is no 
doubt that the cattle were directly concerned in their introduction. In¬ 
deed, without them the seeds, even if accidentally introduced amongst 
the fodder, would not have been placed under such circumstances as 
would have enabled them to give rise to plants. In the first place, by 
being passed through the animals the seeds were softened and the 
period of germination hastened. In the second place the seeds had a 
suitable medium to promote germination, and this enabled the young 
plants to withstand the season of drought which is incidental to almost 
every tropical country. In this instance we have cattle not only the 
means of introducing the seeds of a valuable tree, but also involuntarily 
instrumental in establishing the tree in a new country, and providing 
shelter, shade, and food for their progeny. Those acquainted with the 
Guango or Hain Tree, as this Pithecolobium is locally called, will fully 
realise its value as a shade and food tree for cattle, and they will also 
appreciate the singular concourse of circumstances by means of which 
such a tree was introduc-d to a new country by the very animals which 
required it most. 
It is possible there may be some who will doubt the possibility of 
seeds retaining the power of germination after undergoing the processes 
of mastication and digestion, and especially in the special case of ru¬ 
minating animals. There is, however, very clear evidence on the subject. 
It is a common occurrence in India to utilise the services of goats to 
hasten the germination of the seeds of the common Acacia arabica, 
known a§ the Babul. This tree belongs to the same natural order as the 
Pithecolobium, and grows in the poorest and driest soils of India. The 
Babul seeds will not germinate readily in the hot weather, and it is the 
regular habit, in order to save a season, for a person desirous of a crop 
of seedlings to make a bargain with a herdsman or a neighbour who 
possesses a flock of goats to quarter them for some days in a small enclosure 
in which they are fed on Babul leaves and pods. The droppings of the 
animals contain a certain number of seeds which are uninjured, and these 
now readily germinate, and give rise to plants the same season. I am 
informed by Dr. Watt that in India “ several other plants are treated in 
the same way.” The seeds of the several species of cultivated Guava 
are hard and do not easily germinate. These, however, are said to ger¬ 
minate more freely and readily when they are picked up in night 
soil. 
While on this subject I would mention that when at St. Helena in 
1883 I expressed some surprise that no attempt was made to utilise 
“ urban ” manure in the neighbourhood of Jamestown, when the land 
was so impoverished and yielded such poor crops. I was met by the 
fact that if such manure was largely used the land would become 
overrun with plants of the Prickly Pear (Opuntia Ficus-indica), the fruit 
of which is largely consumed by the inhabitants. There is little doubt 
that the seeds of this plant, like those of the Guava, and I suspect also 
species of Passiflora, which are swallowed whole, are capable of 
germination after they have passed through the human body. Another 
instance occurs to me where the use of manure has been the means of 
distributing an undesirable plant on cultivated lands. In many tropical 
countries a Grass known as Para, Mauritius, or Scotch Grass, and some¬ 
times as Water Grass (Panicum barbinode), has been introduced from 
Brazil, and highly esteemed for its rapid growth and nourishing pro¬ 
perties. It grows well in moist situations, on the banks of streams, and 
even in soils so swampy as to be suitable for nothing else. In such 
situations it spreads rapidly and yields abundant food for cattle and 
horses. Nothing, however, could be worse than this Grass for cultivated 
areas, where the land is required to be kept free from weeds, and where 
crops of Sugar Cane, CoSee, Tea, and Cacao are raised. It has been 
found that where animats are fed on this Grass the joints even after 
passing through the animals have been known to grow. Hence the 
manure, if freshly used, has been the means of establishing the plant 
over wide areas. 
In a recent work Mr. Ball has drawn attention to numerous introduced 
plants which are met with in South America. He naturally mentions 
the Cardoon, the wild state of the common Artichoke, which is now 
more common in temperate South America than it is anywhere in its 
native home in the Mediterranean region. Darwin doubted whether 
any case exists on record of an invasion on so grand a scale. Several 
hundred square miles are covered with this introduced plant, which has 
overrun all members of the aboriginal flora. The introduction of the 
Cardoon appears to have been cfiected directly by man for the purpose 
of contributing to the food supply of cattle ; but as regards another 
widely spread plant the mode of its introduction is not clearly known. 
Mr; Ball states “ As to many of these [introduced South American 
plants] it appears to me probable that their diffusion is due more to the 
aid of animals than the direct intervention of man. This is specially 
true of the little immigrant which has gone farthest in colonising this 
part of the earth—the common Stork’s-bill (Erodium cicutarium), 
which has made itself equally at home in the upper zone of the Peruvian 
Andes, in the low country of Central Chili, and in the plains of North 
Patagonia. Its extension seems to keep pace with the spread of domestic 
animals, and as far as I have been able to ascertain it is nowhere 
common except in districts now or formerly pastured by horned cattle. 
It is singular that the same plant should have failed to extend itself in 
North America, being apparently confined to a few localities. It is now 
common in the Northern Island of New Zealand, but has not extended 
to South Africa, where two other European species of the same genus are 
established.” 
Erodium as a genus is separated from the true Geraniums amongst 
other reasons on account of the tails of the carpels being bearded and 
spirally twisted on the inside. It is possible that these characteristics 
have enabled the seeds to attach themselves to the legs and bodies of. 
cattle, and so effected their distribution over wide areas in such situations 
as are favourable to their growth. 
In the Island of Jamaica we have a remarkable instance of tl® 
naturalisation and wide distribution of an introduced plant in the cas® 
of the Indian Mango. In an official report, published in 188.5,1 stated that 
to the Mango, possibly more than any tree in the island, is due the re¬ 
foresting of the denuded areas in the lower hills ; and as in consequence 
of the changes taking place in the climate members of the indigenous 
flora are unable to maintain their ground, it is fortunate the island 
possesses in a vigorous and hardy exotic like the Mango the means of 
counteracting the baneful effects of deforestation. It specially affects 
land thrown out of cultivation, and the sides of roads and streams 
where its seeds are cast aside by man and animals. It practically re¬ 
clothes the hills and lower slopes with forest, and it enables the land to 
recuperate its powers under its abundant shade-giving foliage. It is 
strange that in Ceylon, which is so much nearer the home of the species, 
the Mango does not spread by self-sown seedlings. This corroborates 
Mr. Ball’s statement with regard to Erodium cicutarium. The latter is 
widely spread in South America, but only sparingly found in other 
countries under apparently exactly corresponding conditions. We 
cannot say why such anomalies exist. They do exist, however, and 
offer problems which can only be solved by a closer study of the con¬ 
ditions of plant life, and the interdependence of plants and animals 
acting and reacting one upon the other.— D. Moeeis (in Nature'). 
WORK.Foi\.THE\)(rEEK.. 
HAHDY FRUIT GARDEN. 
Teaches and Nectaeines. —These flowered very freely, and the 
fruit has set thickly, but unfortunately the foliage is much crippled and 
dirty. We kept the blinds and fish nets over the trees longer than usual 
in order to screen them somewhat from the cold easterly winds, though 
this docs not appear to have done much good. There are many more 
swollen and curled leaves than usual, and these ought to be at once 
picked, as if left on the trees they do more harm than good. A con¬ 
siderable number of the worst placed and all deformed fruits should be 
removed at the same time, and where there are plenty of shoots these 
also may well be thinned. What is wanted is one good shoot at the 
extremity of each piece of young wood, and another as near the base as 
