OF NATURAL HISTORY. 295 



the new infeft is furnilhed with both finooth and convex eyes, to 

 the number of feveral thoufands. 



The internal parts of the infed; have likewlfe undergone as many 

 changes as the external. The texture, the proportions, and the 

 number of the rifcera, are greatly altered. Some have acquired an 

 additional degree of confillence; others, on the contrary, are render- 

 ed finer and more delicate. Some receive a new form, and others 

 are entirely annihilated. Laftly, fome organs in the perfect infed, 

 which feemed formerly to have no exiftence, are unfolded, and be- 

 come vifible. The mod important of this laft kind are the organs 

 of generation. The caterpillar, the nymph, and the chryfalis, were 

 of no fex. But, after transformation, both fexes are diftinguifliable, 

 and the animals are capable of multiplying their fpecies. 



We fhall now give fome examples of transformations which de- 

 viate from the common mode. 



Some Infeds hold a middle rank between thofe which preferve 

 their original figure during life, and thofe that fuflFer transforma- 

 tions. Their exiftence is divided into two periods only. They 

 walk in the firft, and fly in the fecond. Thus their only metamor- 

 phofis confifts of the addition of wings, the growth and expanfion 

 of which are pei formed without any confiderable alteration in the 

 figure of their bodies. 



There is not a law eftablifhed among organized bodies which 

 feems to be fo univerfal, as that all of them grow, or augment in 

 fize, after birth, till they arrive at maturity. If a hen were to bring 

 forth an egg as large as her own body, and if this egg, when hatch- 

 ed, were to produce a bird of equal dimenfions with either of the 

 parents, it would be confidered as a miracle. But the fpider-Jly, fo 



denominated 



