754 



THE POPULAR SCIENCE MONTHLY. 



ment of this century broached the doctrine 

 that there is in living beings a continuous 

 series of gradations as well as a consistent 

 and general plan of organization ; and that 

 the creation, therefore, or origin of the dif- 

 ferent forms of plants and animals must have 

 been the result of a gradual process of de- 

 velopment or of derivation one from another, 

 the whole standing connected together in 

 cei'tain causal relations. But in Britain such 

 views, tliough known and not altogether re- 

 pulsive to a few, obtained little favor, and, 

 by some strange process of reasoning, were 

 looked upon by the great majority as little 

 short of impious questionings of the supreme 

 power of the Almighty. 



" How different is the position of matters 

 in this respect in our day ! when the cau- 

 tious naturalist receives and adopts with 

 the greatest reserve the statement of fixed 

 and permanent specific characters as belong- 

 ing to the different forms of organized beings, 

 and is fully persuaded of the constant ten- 

 dency to variation which all species show 

 even in the present condition of the earth, 

 and of the still greater liability to change 

 which must have existed in the earlier pe- 

 riods of its formation when the belief pre- 

 vails that so far from being the direct prod- 

 uct of distinct acts of creation, the various 

 forms of plants and animals have been grad- 

 ually evolved in a slow gradation of increas- 

 ing complexity ; and when it is recognized 

 by a large majority of naturalists that the 

 explanation of this wonderful relation of 

 connection between previously-existing and 

 later forms is to be found in the constant 

 tendency to variation during development 

 and growth, and the perpetuation of such va- 

 riations by hereditary transmission through 

 successive generations in the long but in- 

 calculable lapse of the earth's natural muta- 

 tions. These, as you must all be aware, are 

 in their essential features the views now 

 known as Darwinism, which were first simul- 

 taneously brought forward by Wallace and 

 Darwin in 1858, and which, after being more 

 fully elaborated in the works of the latter 

 and ably supported by the former, secured, 

 in the incredibly short space of ten or twelve 

 years, the general approval of a large por- 

 tion of the scientific world. The change of 

 opinion is, in fact, now such that there are 

 few scientific works on natural history, 

 whether of a special or more general charac- 

 ter, in which the relation whicli the facts of 

 science bear to the newer doctrines is not 

 carefully pointed out; that, with the gen- 

 eral public too, the words 'Evolution' and 

 'Development' have ceased to excite the 



feelings, amounting almost to horror, which 

 they at first produced in the minds of those 

 to whom they were equally unfamiliar and 

 suspicious ; and that even in popular litera- 

 ture and ephemeral effusions direct or met- 

 aphorical illustrations are drawn in such 

 terms of the Darwinian theory as ' struggle 

 for existence,' ' natural selection,' ' survival 

 of the fittest,' ' heredity,' ' atavism,' and 

 the like. 



" It caqpot be doubted that in this coun- 

 try, as on the Continent, the influence of au- 

 thority had much to do with the persistence 

 of the older teleological views ; and, as has 

 been well remarked by Haeckel, one of the 

 ablest and keenest supporters of the modern 

 doctrine, the combined influence more espe- 

 cially of the opinions held by three of the 

 greatest naturalists and biologists who have 

 ever lived, viz., Linnaeus, Haller, and Cu- 

 vier, men unsurpassed in the learning of 

 their time, and the authors of important dis- 

 coveries in a wide range of biological sci- 

 ence, was decidedly adverse to the free cur- 

 rent of speculative thought upon the more 

 general doctrines of biology. And if it were 

 warrantable to attribute so great a cliange 

 of opinion as that to which I have adverted 

 as occurring in my own time to the influ- 

 ence of any single intellect, it must be ad- 

 mitted that it is justly due to the vast range 

 and accuracy of his knowledge of scientific 

 facts, the quick appreciation of their mutual 

 interdependence, and above all the unexam- 

 pled clearness and candor in statement of 

 Charles Darwin. 



" But while we readily acknowledge the 

 large share which Darwin has had in guiding 

 scientific thought into the newer tracts of 

 biological doctrine, we shall also be disposed 

 to allow that the slow and ditficult process of 

 emancipation from the thralldom of dogmatic 

 opinion in regard to a system of creation, 

 and the adoption of large and independent 

 views more consistent with observation, rea- 

 son, philosophy, and religion, has only been 

 possible under the effect of the general prog- 

 ress of scientific knowledge and the acquisi- 

 tion of sounder methods of applying its prin- 

 ciples to the explanation of natural phenom- 

 ena." 



President Thomson's address con- 

 cludes with the following words: "I 

 consider it impossible, therefore, for 

 any one to be a faithful student of em- 

 bryology, in the present state of science, 

 witliout at the same time becoming an 

 evolutionist. There may still be many 



