in the Reconstruction of extinct Vertebrate Forms, 487 



Mr. Huxley then brings certain other considerations to bear. 

 Taking the case of a crustacean fossil impression, he shows that 

 the restoration of the extinct form is founded on the invariable 

 concurrence of the peculiar many-ringed body and jointed limbs, 

 with a certain form of the jaws, and certain relations of the 

 muscles, nervous system, and other internal organs, to the exo- 

 skeleton. He adds, '^For any physiological necessity to the 

 contrary, the creature might have had its mouth, nervous system 

 and internal organs arranged like those of a fish/' The general 

 statement is quite correct, but the corollary is a manifest fallacy; 

 for if, in the adduced instance, the creature had had its mouth, 

 nervous system and internal organs arranged like those of a fish, 

 it would have ceased to be a crustacean and have become a fish. 

 Mr. Huxley, with the skeleton of a hawk before him, might as 

 w^ell say that, for any physiological necessity to the contrary, that 

 creature might have its jaws with teeth, and its internal organs 

 arranged, like those of a tiger. Nature has formed living beings 

 upon certain types, which constitute the basis of methodical 

 nomenclature, and the correlation of part to part, and organ to 

 organ, is adjusted in subordination to those types. 



The fallacy involved in his next instance is still more obvious: 

 '' If we turn to the botanist, and inquire how he restores fossil 

 plants from their fragments, he will say at once, that he knows 

 nothing of physiological necessities and correlations. Give him 

 a fragment of wood, and he will unhesitatingly tell you what 

 kind of a plant it belonged to ; but it will be fruitless to ask him 

 what physiological necessity combines e. g. peculiarly dotted 

 vessels with fruit in the shape of a cone and naked ovules, for 

 he knows of none. Nevertheless his restorations stand on the 

 same logical basis as those of the zoologist. 



" Therefore, whatever Cuvier himself may say, or others may 

 repeat, it seems quite clear that the principle of his restorations 

 was not that of the physiological correlation or coadaptation of 

 organs. And if it were necessary to appeal to any authority 

 save facts and reason, our first witness would be Cuvier himself, 

 who in a very remarkable passage two or three pages further 

 on ('Discours,' PP- 1^^^ 1^^) implicitly surrenders his own 

 principle.^' 



Now, plants have only organic or vegetative life, limited to 

 nutrition and reproduction. But animals, besides this organic, 

 have sensorial life superadded. Supposing a question were 

 raised as to the reality of sensorial life, what would be thought 

 of the naturalist who would turn to the botanist and say, 

 " Your plants assuredly have not got sensation, perception, and 

 voluntary motion, therefore animals are not likely to have 

 them" ? The argument drawn by Mr. Huxley from instances 



