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THE GOMESS PROCESS FOR THE PREPARATION OF RHEA
OR RAMIE FIBRE. WHAT promises to be a new industry of almost incalculable proportions for India has been rendered possible by the recent discovery of a method of separating the silky fibres of the bark from the outer cuticle and the gummy tenacious matters in which they are embedded.
This separation has been hitherto effected by hand, many mechanical devices having been tried, and rejected on account of their cost. Large rewards have been offered by the Indian Government for a successful process, but the hand method, though laborious and slow, has hitherto held the field.
The difficulty of separating the fibre has, it is said, been at last successfully overcome by a purely chemical method, discovered by an Indian-born chemist, Mr. Gomess, which consists chiefly in removing the foreign matters by means of a solution of zincate of soda. It is thus obtained on washing perfectly free from resin and ready for the comb.
Although the descriptions of the method which I have so far been able to obtain are not very precise, I have been able to prepare a fairly presentable specimen of the fibre by means of zincate of soda from Rhea grown at the Wollongbar Experiment Station, and shall be glad to show it to anyone interested in the matter.
Forest Moths that have become Orchard and
BY WALTER W. FROGGATT, Government Entomologist.
The inroads that many moths, whose natural food-plants are in our bush, are making into the orchards and gardens of New South Wales, is a subject well worthy of investigation.
For some years I have studied the habits of these moths, and in the hope that I may be the means of assisting our fruit-growers and gardeners to combat this evil, I have prepared a series of papers which will comprise a complete illustrated account of the life histories of these insects, with suggestions as to preventive measures and treatment. My notes have been made upon specimens which have been kept under observation in the Technological Museum until they have completed their metamorphoses, and most of the larvæ have been collected in the neighbourhood of Sydney.
The Painted Acacia Moth (Teia anartoides, Walk.) The caterpillar of this handsome little moth is one of the most destructive creatures found about Sydney, and is common all over New South Wales and Victoria. In its native state it feeds upon the foliage of a number of different species of wattles, especially the soft-leaved wattle (Acacia pubescens), and the black wattle (Acacia decurrens), but it is now almost omnivorous in its habits. I have received specimens from Armidale, where the caterpillars have completely stripped cherry-trees of their leaves in several orchards. In gardens around Sydney it has attacked the foliage of rosebushes and pelargoniums.
From Mr. H. G. Smith, of Tempe, I received several branches of golden wattle (Acacia pycnantha) swarming with these hairy little caterpillars, which had gnawed off the upper surface of the leaves, and caused them to curl up and wither. In this instance the pests were fortunately attacked by a small parasitic wasp-a dainty little fellow, with long slender black antennæ, slender stalked body, fine gauzy wings, and bright yellow legs; belonging to the small ichneumon flies of the family Braconide.
It was evident that the wasps deposited their eggs upon the back of the caterpillars when the latter were very young, as before they were half grown, the wasp larva had eaten up its host and spun a stout silken cocoon covered with the skin of the caterpillar, and attached to the nearest twig.
Upon emerging from the eggs the caterpillars are almost black, but by the time that they have grown a quarter of an inch in length they begin to assume a browner tint, chiefly from a number of grey tubercules or warts appearing along the sides of the body.
They are now thickly clothed with long hairs, with two curious round redcoloured appendages projecting from the back near the tail. When full
Reference to Plate. -A, Female moth or cocoon ; B, Male moth; c, Caterpillar.
grown the caterpillar measures about 14 inch in length, and is rather slender in shape, with the legs and claspers reddish yellow. The head is dull, reddish brown, lightly covered with long greyish hairs, with a slender tuft projecting from each shoulder beyond the head, the tip of each of these long hairs forming a swollen lance-shaped point. Along the centre of the back, from the centre of the first four abdominal segments there is a thick erect brush-like bunch of greyish brown hairs, the thoracic segments in front of these tufts being marked with yellow, and the whole of the upper surface of the caterpillar is covered with long brown hairs, and patches of shorter grey hairs along the sides, a large projecting plume being formed on either side towards the tip of the abdomen. All these hairs are very finely feathered, which gives them a downy appearance.
When full grown they crawl into any corner and spin a loose, light brown silken cocoon of a very flimsy character, through which the pupæ can be plainly seen, and it will be noticed that more than half of them are fully twice the size of the others, the larger being the females. In the summer time they do not remain in the pupal state longer than a fortnight, but in the winter broods not only do the larvæ feed much longer, but the pupal stage lasts until the summer months come round. The male moth measures about an inch across its outspread wings, of which the fore pair are dark brown, marbled with vellow and grey markings, with a very black transverse band across the tip, and a patch of the same colour at the base of the wings. The hind wings are bright orange yellow in the centre, with a broad black band encircling them, fringed along the outer edge with yellow. The body is rather pointed towards the tip, while the thorax is stout; the antenna short, broad, and beautifully feathered. When the moth is at rest, it clings to the branch or wall with the wings pressed down on either side forming an angle broadest at the base.
The female moths are short, rounded creatures destitute of wings, with the antennæ and legs rudimentary, but thickly clothed all over with short brown down. Their life work is very limited, for they simply crawl out of their shelter, lay their eggs upon the top of it and die.
The eggs are dull white, hemispherical in shape, and showing a beautiful fascetted structure under a lens. They are rather large for the size of the moth, and generally matted together with the down from the moth's body. Each moth lays on an average about 700 eggs, so it is easily seen how rapidly a family of these moths can increase, particularly as they have several broods in the year.
Prevention and Remedy.—The fact that the larvæ crawl into any sheltered place to spin their cocoons, often congregating in considerable numbers, when the trees are badly infested, would suggest the advisability of binding several “burlaps ” round the trunk and larger limbs just before the caterpillars commence to pupate. A "burlap" bandage differs from the ordinary bandage used for trapping the codling moth, in being tied rather loosely round the centre with the upper half turned down over the twine, forming 1 more roomy hiding-place than the codling moth grubs require.
This burlap band has been tried with great success by the Commission appointed by the Massachusetts Board of Agriculture in destroying the very similar larvæ of the Gypsy Moth, which has caused much destruction both to fruit and forest trees.
The caterpillars would naturally come into these shelters, which could be examined regularly, and replaced to gather in those still feeding. In isolated cases where a single tree is infested, this would be a very cheap and simple method of destruction, and with a little care very few would escape.