Birds. 7731 



" Does what the insects have spared remain to the agriculturist ? 

 No ; a multitude of moles, field-mice and rats, after having lived in 

 the fields to the detriment of the harvest, enter the granary and levy 

 a new tax upon it. 



" Who could calculate the losses which result to Agriculture from 

 all these united causes ? 



" It is only for a few years that Science has understood that it 

 had a great social duty to fulfil ; it is but yesterday, so to speak, 

 that these questions have been studied; statistics, therefore, as 

 yet, only provide incomplete data, which must not be quoted too 



hastily. 



" Nevertheless, the complaints of the vine-growers attest the enor- 

 mous extent of the evil in that particular branch of cultivation. 



" As regards grain {Cerealia), the amount destroyed in one single 

 year in one of our eastern departments, by the larva of a Cecidomyia, 

 is estimated at four millions of francs (£160,000).* 



" In a special notice, and according to a great number of facts care- 

 fully studied, M. Bazin does not hesitate to attribute to this insect the 

 insufficiency of the harvests from which we sufifered so much in the 

 three years which preceded 1856 ; in many fields the loss was more 

 than half the crop.f 



" As regards rape, a Report, veiy ably drawn up by one of the 

 Professors of the old Agricultural Institution of Versailles, has shown, 

 by most carefully made investigations on a crop belonging to that esta- 

 blishment, that on twenty pods taken by chance and giving 504 grains, 

 only 296 grains were healthy ; the remainder were eaten up by insects 

 or destroyed by their contamination : that, consequently, there was a 

 loss in oil of 32-8 per cent. ; and more especially on a harvest which 

 produced 4500 francs it was necessary to calculate a loss of 2700 

 francs, which, could it have been avoided, would have realized 7200 

 francs.]: 



"In Germany, according to Latreille,the Black Arches moth {Orgyia 

 monacha) has destroyed whole forests. § In 1810 a species of Bostri- 

 cbus had so invaded' the forests of Tannebuch, in the department of 



« * ' Ami des Sciences' of August 9, 1857. 



« t ' Notice of an Insect which has caused the greatest Ravages among our 

 standing Crops.' Parisj 1856. 8vo, 32 pages, with plates. 



"+ M. Focillon, ' Des Insectes qui nuisent au Colza.' Paris, 1851. 41 pages 

 4to, and plales. 



"§ Latreille, ' Histoire des Insectes.' 



