NA TURE 



385 



THURSDAY, AUGUST 22, li 



AFRICAN FARM PESTS. 



Notes ami Descriptions of a Few Injurious Farm and 

 Fruit Insects of South Africa. Compiled by Eleanor 

 A. Ormerod, F.R.Met.Soc, &c. (London : Simpkin, 

 Marshall, and Cq., 1889.) 



MISS ORMEROD is indeed energetic. Not content 

 with waging bitter war against the destructive pests 

 of British crops, she extends her campaigns to far distant 

 lands. Although applications of farmers for information 

 as to the attacks of many injurious insects arrive inces- 

 santly from all parts of the United Kingdom, Miss Ormerod 

 finds time to deal with the complaints of cultivators in all 

 other parts of the world, and surveys insects from China 

 to Peru. In 1887 an elaborate treatise upon a scale- 

 insect {Icerya purchasi) which seriously injures vines, fig, 

 orange, peach, and other trees and shrubs in Australia, 

 was published by Miss Ormerod, giving full scientific 

 details as to the life-history of this coccid, and as to 

 methods of prevention and remedies likely to be beneficial. 

 Just recently another work has appeared, entitled" Obser- 

 vations on some Injurious Insects of South Africa," written 

 in Miss Ormerod's usual clear and interesting style, and 

 admirably illustrated. From this we propose to take 

 some extracts to show the cosmopolitan entomological 

 knowledge of the authoress, as well as to give some idea 

 of the enemies of cultivated plants in "Afric's golden 

 sands." 



The first reflection that arises from the perusal of this 

 book, and of others descriptive of the usual plagues which 

 follow in the wake of civilized cultivation, is that no clime 

 nor culture under the sun is exempt from them. No 

 sooner had orange groves been formed in the suitable 

 lands of Florida than various scale-insects swarmed upon 

 the trees. The purple scale, the white scale, the red scale, 

 and the " chaff" scale, among others, threatened to ruin 

 the crops and to kill the trees, until remedies were dis- 

 covered by the skilful economic entomologists of the 

 United States. 



In the newly made tea plantations of Assam a red 

 spider (Tetranychus bioculatus) has suddenly shown 

 itself, and threatens serious mischief to the plants, unless 

 some wash can be invented which will kill the spiders, and 

 leave no taste in the tea-leaves. 



So in Africa, scale-insects, especially the Icerya pur- 

 chasi, have within the last few years, as shown by Miss 

 Ormerod, extensively spread in Cape Colony, upon 

 oranges, lemons, vines, and other kinds of fruit-trees. 

 This scale-insect has also now become one of the most 

 dangerous pests infesting fruit-trees in California. It is 

 the opinion of Prof Riley, the United States Entomologist, 

 that the Icerya purchasi originated in Australia. There 

 was some doubt at first as to this. It was thought that it 

 came from Mauritius ; but it was discovered that it was 

 the species known as Icerya sacchari which was imported 

 from thence upon sugar-canes to California. 



Frequent and rapid communication between countries, 



and the general interchange of commodities of all kinds, 



have undoubtedly disseminated insects throughout the 



world. Thus the Hessian fly was brought from the 



Vol. XL. — No. 1034. 



United States with straw in packing-cases, and the flour 

 moth {Ephestia kuhtiiclla), has been recently imported 

 into England from some European country, as the 

 authorities conclude. 



At the same time it is considered that the conditions 

 of cultivation adopted in these days, being somewhat of 

 a forcing and unnatural nature, favour the increase of 

 insects, and, in a degree, predispose plants to their 

 attacks, which become more varied and intensified year 

 by year not only in this country but in all others. It is 

 of the greatest importance, therefore, that cultivators 

 should be advised by competent persons as to the life- 

 histories of these crop destroyers, and as to measures to 

 be taken to prevent their spread, and remedies to be 

 used against them. 



Miss Ormerod has arisen, a very Dea ex machind, and 

 for several years has given timely instruction and advice 

 to agriculturists of many nations, just as Professors Riley, 

 Lintner, and Comstock have helped the tillers of land in 

 the United States to detect and combat the onslaughts of 

 many crop-destroyers. Prof. Lindeman is doing the 

 same good work in Russia, Dr. de Man in the Nether- 

 lands, Dr. Taschenberg in Germany. 



And in this her latest work, " Notes and Descriptions 

 of Injurious Farm and Fruit Insects of South Africa," 

 Miss Ormerod conveys much practical information which 

 can be readily understood and easily utilized. At the 

 same time it is scientific enough for entomologists, and 

 interesting to those who are not cultivators or men of 

 science. 



Miss Ormerod explains her reasons as follows for pub- 

 lishing this account of African farm pests, though no ex- 

 planation appears necessary for such a valuable service : — 



"About four years ago, Mr. J. D. Bristow, President of 

 the East Province Natural History Society of Cape 

 Colony, wrote to inquire whether, if I were furnished with 

 notes regarding pests of the crops in East Province, Cape 

 Colony, I would publish them. At that time there was 

 not the opportunity which there now is of procuring 

 sound and clear directions for treatment of insect as well 

 as other attacks of crops and stock, by reference to the 

 Agricultural foiirnal, published by the Department of 

 Agriculture of Cape Colony, therefore I willingly agreed 

 to do my best, in case trustworthy agricultural observa- 

 tions could be procured, and specimens of the insects 

 referred to also sent for identification. Specimens of 

 about fifty kinds of insects were sent over, of which a few 

 proved to be of undescribed species ; and I have given in 

 the following pages, as far as I can, figures and observa- 

 tions of habits and means of prevention of some of the 

 pests, and means by which they might be identified." 



The first insect described is one of the well-known 

 dangerous family Mclolonthidcc, to which the familiar 

 British cockchafer belongs. The scientific name is 

 Eriesthis stigmatica, but it is commonly termed the 

 " mealie," or maize, chafer, as it is the worst pest in the 

 country for crops of maize, and destroys it from near Fort 

 Beaufort right down to the Fish River mouth. This is 

 very much smaller than the cockchafer, and smaller, too, 

 than the rose chafer {Cetonia aurata), which is, however, 

 of a different family. 



Another chafer, HypopJiolis sommeri, injures vines con- 

 siderably, probably by devouring the leaves, in the perfect 

 state, and feeding on the roots, in the larval state. It is 



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