GENERATION OF INSECTS. 23 



them back to the side of a very large pond, which, in 

 spawning time, he was informed, swarmed with count- 

 less numbers of frogs. He naturally concluded, there- 

 fore, that, instead of having been prcci|)itated from the 

 clouds, they had been bred in the pond, from which 

 they had been invited a short time before, by a re- 

 freshing shower, to go in quest of food.* Their great 

 numbers will appear less marvellous, when we consid- 

 er that a single frog spawns, as De JMontbeillard in- 

 forms us, about 1300 eggs.t Were it not, indeed, 

 for their numerous enemies, and their not being fit to 

 propagate till they are three years old, the country 

 would soon be overrun with these reptiles. We have 

 more than once seen a similar legion of hair-worms 

 (Gordii aquatki, LiNN.) in a garden at Lee, in Kent, 

 every plant and spot of ground literally swarming with 

 them. Their numbers, however, were easily account- 

 ed for, as a stream at the bottotn of the garden 

 abounds with them, and, like frogs, they appear to be 

 amphibious J 



The errors of theory, as well as the mistakes of 

 observers, swayed (unconsciously perhaps) by the 

 influence of their theoretical opinions, may all be 

 traced, we think, to the propensity of human nature 

 to discover resemblances in things, which are after- 

 wards magnified into close affinity, or even into 

 identity. We are indebted to one of our best living 

 entomologists, INIr W. Mac Leay, for clearly point- 

 ing out the broad distinction between analo^ij and 

 affinity.^ The supposed floating of the eggs of insects 

 in the air thus appears to have originated in drawing 

 an analogy from the seeds of plants; though, from 

 the facts we have stated, so far from there being any 



* Ray's Wisdom of f»od in the Creation, p. 156. 

 t Diet. Clitssique dMlist. .Nat., vii, p. 495. t J. R. 



} Horae Entomologicse, or Essays on Annulose Animals, 8vo. 

 London, 1819-21. 



