340 ON SPONTANEOUS GENERATION. 



motion, which obliges it to several coctions, it turns it pre- 

 sently to a vegetable, or if it makes two coctions, seeing the 

 second has not time enough to receive perfection in, it only 

 engenders an insect." We have here the real spirit of the 

 doctrine laid bare and open to view in its greatest absurdity ; 

 and even the most plausible expositions of spontaneous 

 generation, have no better foundation on which to take their 

 stand ; they are all obliged to have recourse to some assisting 

 power to help them out of their difficulties, knowing that if 

 they rest their doctrine upon the power of matter, the 

 universal experience of all mankind would bely it, they there- 

 fore generally, and most wisely, lay it down, that only the 

 smaller and more simply organized beings are produced by 

 it. The difficulty, then, in refuting it, consists in the greatly 

 enhanced difficulties of observation. When we find that per- 

 sons of eminent rank in science, are at issue respecting the 

 organization of the minute organisms; — that they cannot coin- 

 cide upon what is submitted to the observation of their own 

 eyes; — should itnot induce us to hesitate before we assert that 

 they are positively exempt from the operation of those laws 

 which we find to be universal and absolute in every case of 

 an organism that is fully open to our observations in every 

 succeeding period of its organization ? There are, no doubt, 

 many anomalies in the modus operandi of those laws, but 

 one circumstance is always essential, and that is, a typical 

 predecessor. It is a most mystical occurrence, not to be ac- 

 counted for in our present state of physiological knowledge, 

 that an organism should propagate itself by bodily division, 

 or that one impregnation should suffice for several successive 

 generations of Aphides ; but from some cause not yet known 

 (probably from exposure to cold), it requires renovation, 

 which is provided for by the last generation always contain- 

 ing males. In some instances mentioned in Westwood's 

 Introduction, of female moths having firuitful descendants 

 without sexual impregnation, the last generation were all 

 males ; still they remained true to their type ; even all the 

 arts of mankind, exerted upon the most variable species of 

 organisms subject to his controul, with all the diversities of 

 soil, climate, and culture that exist upon the surface of the 

 earth, have been unable to produce a new species ; the most 

 plastic still remains true to its type : even when he forcibly 

 combines two species, and attempts to produce a compound 

 of them, it succeeds not beyond the primary instance, but 

 either remains barren, or breeds back to the type of one of 

 its parents. Do we not perceive that here is a boundary fixed ? 

 Is not here an absolute line of demarcation drawn by some 



