268 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. [September 20,1S7L 
of specimens, leaving- it to the collector to add to the list 
as opportunity offers, and usefulness would suggest. 
1. Samples of crude juice, without any preparation 
whatever, care being taken to place the same immediately 
in air-tight vessels to guard against any spontaneous 
change taking place. If two such specimens can he sent, 
to one might he added a small quantity of ammonia, as 
this checks coagulation. Care should he taken to ex¬ 
clude light. 
2. Samples of rubber, prepared in as many different 
ways as possible, such as those enumerated, care being 
taken to note the time occupied, and which gives the 
best result in quality and quantity, a uniform quantity 
being used in each trial. 
3. Samples of the whey-like substance which separates 
from the india-rubber during its coagulation. 
4. Samples of prepared rubber in the form or forms 
proposed to export it in, care being taken that it is as 
clean and dry as possible. 
5. Note the average yield of each kind of tree, and the 
relative yield by simple tapping; 2, tapping, aided by 
binding; and 3, total destruction, the best season to con¬ 
duct the operation, the effect of tapping on the vitality 
of the trees, the period of rest required. Of course 
neither binding nor total destruction should be had re- 
course to in practice. 
Specimens, illustrating such notices, would be exceed¬ 
ingly useful. 
Our knowledge of the botanical origin of many of the 
milky juices needs much enlightenment; and it is highly 
desirable that complete series of botanical specimens 
should be obtained. The following is a list of specimens 
which should be collected in order to be as complete as 
possible. 
1. Dried specimens of a branch, having the leaves, 
flowers and fruit attached. These may easily ho dried 
between sheets of any porous paper, care being taken to 
change the paper a few times at first to ensure perfect 
dryness, and to guard against mouldiness. The speci¬ 
mens should be as characteristic of the tree as possible— 
leaves on different parts of a tree in some instances vary 
considerably. 
2. Specimens of leaves, flowers and fruits attached, 
preserved in a jar or bottle, in some spirit, such as 
brandy, spirits of wine, or acetic acid, and tightly corked 
and secured to prevent leakage. 
3. Specimens of the wood and bark and india-rubber 
gathered from the same identical tree. 
4. Where there is more than one kind or variety of 
tree yielding the same substance, complete specimens of 
each kind or variety should be sent. 
I shall be happy to receive and report on any such 
series of specimens, and will gladly acknowledge them 
in any future papers on the subject I may publish.— 
S. IF. Silver and Co.'s ‘ Colonial News, London. 
REARING GF THE COCHINEAL INSECT IN THE 
CANARY ISLANDS. 
In the Canary Islands the rearing of the cochineal in¬ 
sect, for the purpose of export, is carried on to a con¬ 
siderable extent, and forms the bulk of the contribution j 
from these islands towards supplying the necessities of; 
commerce. According to the official returns for 1869 the 
quantity of cochineal exported thence during that year 
amounted to 6,316,000 lb., tho estimated value being; 
£842,921. Of this quantity, no les3 than 4,232,600 lb., | 
valued at £554,092, was exported to England. Some | 
idea of the development of this industry may bo formed 
from the fact that the exports, which in 1865 were under 
2,400,000 lb., had increased, in 1867, to over 5,000,000 
lb., and, in 1869, to 6,316,000 lb., more than half of 
which was exported from tho island Grand Canary. In 
fact, cochineal rearing'is so profitable and is augmenting 
so fast, that it attracts all the available capital in the 
island. A consequence of this is, that the necessaries of 
life, which were formerly produced in those islands in 
great abundance, are no longer to be obtained in suffi¬ 
cient quantity to meet the wants of tho population, ex¬ 
cept at a greatly increased price. Steps have therefore 
been taken by the provincial authorities to obtain from, 
the Spanish Government permission to import from 
Morocco live-stock and other articles of consumption. 
A very interesting report on the method of rearing tho 
cochineal insect in the Canarv Islands has been furnished 
by Mr. Consul Grattan, from which we abstract tho 
following particulars:— 
The cochineal insect is a species of coccus about tho 
size of a pea; it has a silvery grey appearance, the body 
being reddish-black and covered with fine white dust. 
When first brought forth the insect moves about freely, 
but as it grows it fixes itself to the leaf from which it de¬ 
rives its nourishment. There are several varieties of the 
prickly pear plant on which the cochineal feeds, but that 
most generally cultivated for the purpose of breeding is 
the common hardy Cactus opuntii. In a wild state this 
plant brings forth abundance of fruit, and it formerly 
supplied one of the principal articles of food to tho inha¬ 
bitants of the Canary Islands. The fruit is found to de¬ 
bilitate the plant when used for the purpose of rearing 
cochineal, it is therefore carefully removed as fast as it 
buds. The cactus plant is so hardy as to grow luxu¬ 
riantly on rocky spots, where there appears to be scarcely 
soil enough to fill tho crevices; but in this state it cannot 
servo for the rearing of cochineal for more than one or 
two seasons. In rich soil, and with abundance of manure 
and water, the same plants will continue to yield excel¬ 
lent crops for from ten to twelve years. 
The best soil is that which is found in volcanic- 
countries, where pumice stone and black scoria abound- 
Where no artificial irrigation can be obtained, a layer- 
of black scoria, called here “picou,” covering the ground 
to the depth of several inches, is found greatly to im¬ 
prove the plant, by retaining the moisture of the soil 
and protecting it from the heat of tho sun, and also by 
preventing the growth of weeds, thereby keeping the 
land constantly clean. In those parts of the Canary 
Islands where the soil has been overrun by lava, and on 
which the vegetable growth is confined to lichens, mosses- 
and here and there small ferns or weeds, the preparation, 
of the land for the cultivation of the cactus is a long and 
costly process, the expense of the process varying ac¬ 
cording to the hardness of the rock, to the abundance of 
subsoil, and to many other circumstances. Where there- 
is abundance of earth on the surface, and the preparation 
consists only in levelling the ground for the facility of 
planting and of irrigation, tho cost is much less, but a 
thorough upturning and airing of the soil is found to bo 
essential to the successful cultivation of the cactus. The- 
cactus plant is propagated by the leaves, wdrich are 
broken off sharply one at the time, and exposed to tho 
heat of the sun for about three weeks before they are 
planted; if the leaf is put into the ground fresh and 
moist as at first gathered, it is almost sure to rot; but 
when allowed to dry in the sun until slightly bent, it 
will strike root and bud with facility. During the sum¬ 
mer months, leaves so dried will be found to bud in ten 
days or a fortnight with great profusion, as many as- 
eight or ten new leaves bursting forth at the same time. 
They are planted in furrows at about a yard apart, either 
edgeways, as close as possible, or about four inches apart 
if placed across the furrows. This is done in May or 
June; in four or five months the new leaves wall have 
grown to their full size, and the plants will then bo 
ready for transplanting. Here the furrows are at least 
two yards apart, in order to admit of a free passage to- 
the labourers amongst the plants after they have grown 
to their full size; and each plant is placed half a yard, 
from that on either side of it, to allow sufficient space? 
