8 



successive generations, it would have spread over the 

 whole globe, had it not been restrained and confined 

 within narrow hmits by insuperable geographical and 

 physical barriers. From a careful comparison of the 

 insects of our own country with those of other parts 

 of the world, I am fully convinced that these laws 

 are founded in nature, and can venture to assert that, 

 with the exception of the polar species, there are no 

 insects in America identical with those of the Eastern 

 continent, which have not accompanied man and his 

 imports from thence. 



The introduction of foreign insects, in a country 

 before uninhabited by them, is a circumstance of more 

 importance, than at first would be anticipated. It may 

 occur in various ways. Man, in his wanderings and 

 migrations, has been instrumental in the dispersion and 

 colonization of a multitude of insects. They adhere 

 to his garments and bedding, riot in his stock of pro- 

 visions, and lurk among his imported seeds, fruits, 

 plants, and drugs. The bed-bug, the flea, the cock- 

 roach, the bacon-grub,* and the meal-worm f have been 

 universal travellers, and are now citizens of the world. 

 Commerce brought the first of these insects to England 

 from the continent at an early period. J " The Scotch, 

 it has been said, "bewail its introduction among them 

 as one of the evils of the union, and for that reason dis- 

 tinguish it by the name of the English bug." Kalm § 

 observes, that it was unknown to the northern Indians 

 of America. The common house-fly || is stated to have 



* Dermestes lardarius. L. t Tenehrio molitor. L. 



X See " A Treatise on Bugs, by J. Southall." 8vo. Lond. 1730. 

 § Travels, ed. 1770. Vol. II. p. H. 

 II Belknap, Hist, of N. Hamp. Vol. III. p. 185. 



