ON EQUIVOCAL GENERATION. 127 



that time they could be kept from sexual intercourse the re- 

 production would cease. 



Dr. Darwin, and all other advocates for spontaneous gene- 

 ration, speaks of some animals as simple and others as complete, 

 some as imperfect and others as perfect; whereas, as far as we 

 can discover, all animals, even the most minute that have been 

 examined, appear to be as perfect, and to have a structure as 

 wonderfully complicated, as the largest, though on account 

 of their minuteness, we cannot dissect them to so much ad- 

 vantage. Their organs are equally adapted to their situations 

 and occasions; and what is more, they have as great a degree 

 of mtcll/gence (which they discover by the methods of seeking 

 their food, avoiding, or contending with their enemies) as the 

 largest animals : besides, it is never pretended that any large 

 species of animals, though called imperfect, as crabs and 

 oysters, &c. are ever produced by spontaneous generation. 



The larger kinds of the more perfect animals Dr. Darwin 

 does not pretend to have ever been " produced immediately 

 " in this mode of spontaneous generation;" but he supposes, 

 what is even more improbable, viz. that " vegetables and ani- 

 " mals improve by re-production; so that spontaneous vitality 

 " (p. 1.) is only to be looked for in the simplest organic be- 

 " ings, as in the smallest miscroscopic animalcules, which per- 

 " petualiy perhaps however enlarge themselves by re-prod uc- 

 " tion; and that the larger and more complicated animals 

 " have acquired their present perfection. by succesive genera- 

 " tions, during an uncounted series of ages." 



13y this he must have meant to insinuate, for it is not clearly 

 expressed (perhaps to avoid the ridicule of it) that lions, horses, 

 and others, which he considers as more complicated animals, 

 though they are not more so than liies and other insects, may 

 have arisen from animals of different kinds, in the lowest state 

 of organization, in fact, that they were once nothing more than 

 microscopic animalcules. 



But this is far from being analogous to any thing that we 

 observe in the course of nature. We see no plants or animals, 

 though ever so simple, growing to more than a certain size, 

 and producing their like, and never any others organized in a 



