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causes to wither. All these garden pests are well kept in check by 
their natural enemies, many of which can be seen on the different 
plants. There are many Brachyacantha ursina and allied species, 
and the black carcasses of the Aphides with a small hole at one end of 
their bodies tell us that the Ephedrus ineompletus Pro v. has found them 
lit subjects for depositing their eggs in. The Coccidre also show para- 
site holes on their scales. A Ghrysopa sp. is quite common here and is 
always found together with the Orthesia on Orotons. 
In our garden at Port of Spain we keep a little Oyprinodonte? sp. 
about 1 inch in length. This little fish is found commonly all over 
the island and I am sending specimens to Prof. C. V. Riley to show 
to the members of the Association. His use is to keep down the 
mosquito larvae in the water tanks, etc. I think this little fish could 
be introduced into America with comparatively little trouble, as he is 
very hardy, standing a degree of heat which would kill most fishes ; 
besides this it is viviparous, so that a few put into a water tank would 
increase without giving any trouble at all. 
Amongst the agricultural pests the first place is taken by the leaf- 
cutting ants (Atta sexdens L.), which is the worst enemy of the cocoa 
plantations. It is found all over the island. The average size of a 
colony of these ants is 1 cubic foot. A nest, as it may be called, 
consists of a number of these colonies near each other, and connected 
by subterranean galleries. The largest nest I have seen covered an 
area of about 2,500 square feet, and must have contained hundreds of 
colonies, each of which possessed a queen. The colonies produce hun- 
dreds of females yearly, which, as soon as the rainy season sets in (about 
May and June), swarm, and a certain proportion of them form new 
colonies. The damage these ants do to young cocoa trees is a source of 
perpetual anxiety to the planters, who spend large sums yearly to have 
the nests destroyed. The method adopted to destroy these ants con- 
sists in " puddling" them, to use the local expression. This process 
consists in digging up the nests, adding plenty of water, and then 
mixing up the ants with the mud, so as to stifle them, and form a 
concrete mass. There are some other remedies used, such as coal tar 
and cyanide of potassium, but they are not attended with good results. 
A Longicorn beetle (Stirastoma depressum) also attacks the cocoa 
trees, preferring the young ones. In some localities it is on the increase. 
The tree this beetle attacks in the woods by preference is the Pachira 
aquatica. 
Generally, every year at about the commencement of the rainy sea- 
son, swarms of locusts, belonging to the Acridiidse, suddenly make their 
appearance, and commence attacking the cultivations. The fact of 
the insects being all young tends to show that they are hatched from 
eggs of the year before. They are generally destroyed, so that the 
numbers are well kept in check. 
At the present moment theCoccid, Biaspis boisduvallii, is making its 
