174 ORIGIN OF BLIGHT INSECTS. 



of cough, lumbago, catarrh, and rheumatism to be disputed ; 

 but in common with other things and persons of ill repute, the 

 treacherous East would seem to bear the burthen of other sins 

 besides its own. In addition to the above acknowledged evils, 

 that "Death in the air" which would seem to be really 

 borne upon the wings of this malicious wind, it is popularly 

 accused of bringing "life in the air," but in a form which to 

 the vegetable creation is quite as fully fraught with destruction, 

 as are to the animal its poisonous invisible arrows. Besides 

 these, and almost as impalpable, myriads upon myriads of In- 

 sect eggs, or as some have it, minute Insects, are supposed to 

 float in the blighting atmosphere, whence, falling in showers on 

 the verdant face of nature, they soon become visible in the 

 shape of our Aphis marauders, or of leaf-destroying caterpillars. 

 "With the fact, however, that Insect eggs are heavier than 

 water,* the notion of their floating through the air is not quite 

 accordant ; or granting that they float, from whence they origi- 

 nally came, is still - the posing question : a question best 

 answered, perhaps, by the plain and probable inference 

 (adopted by Eennie and other naturalists) that neither our 

 blight Insects, nor their eggs, have ever been aerial travellers ; 

 but that from innumerable minute eggs, laid in autumn on the 

 trunks or branches of tree or shrub, or upon some adjacent 

 objects, they emerge almost simultaneously in spring. Their 

 amazing number is sufficiently accounted for, when we find 



* Kennie, Insect Transformations, p. 16. 



