50 NATURAL THEOLOGY. 



forms and other species having perished, being, by the de* 

 feet of their constitution, incapable of preservation, or of 

 continuance by generation. 'Now there is no foundation 

 whatever for this conjecture in any thing which we observe 

 in the works of nature ; no such experiments are going on 

 at present — no such energy operates as that which is hero 

 supposed, and which should be constantly pushing into ex- 

 istence new varieties of beings. Nor are there any appear- 

 ances to support an opinion, that every possible combination 

 of vegetable or animal structure has formerly been tried. 

 Multitudes of conformations, both of vegetables and animals, 

 may be conceived capable of existence and succession, which 

 yet do not exist. Perhaps almost as many forms of plants 

 might have been found in the fields as figures of plants can 

 be dehneated upon paper. A countless variety of animals 

 might have existed which do not exist. Upon the suppo- 

 sition here stated, we should see unicorns and mermaids, 

 sylphs and centaurs, the fancies of painters, and the fables 

 of poets, realized by examples. Or, if it be alleged that 

 these may transgress the bounds of possible life and propa- 

 gation, we might at least have nations of human beings 

 without nails upon their fingers, with more or fewer fingers 

 and toes than ten, some with one eye, others with one ear. 

 with one nostril, or without the sense of smelling at all. 

 All these, and a thousand other imaginable varieties, might 

 live and propagate. "VYe may modify any one species many 

 different ways, all consistent with life, and with the actions 

 necessary to preservation, although affording different de- 

 grees of conveniency and enjoyment to the animal. And if 

 we carry these modifications through the different species 

 vvhicl". are known to subsist, their number would be incal- 

 5ulabl '., No reason can be given why, if these deperdits 

 ever existed, they have now disappeared. Yet, if all possi- 

 ble existences have been tried, they m.ust have formed pari 

 of the catalogue. 



But moreover, ^he division of organized substances into 



