222 JOURNAL OF THE ROYAL fiORl^ICUL'TURAL SOClM'Y. 



when studying the alhed plants and animals of South America and ol 

 the Galapagos Islands, my father did not enter on any speculations as 

 to the origin of species as being by " Descent with modificatfon, " 

 except so far as his own experiments with primroses, &c., carried him. 

 These might be called, in de Veies' term, " mutations " or sports, for 

 he thought that the primrose, cowslip, and oxlip were different forms 

 of the same species. He tacitly accepted Humboldt's and Sedgwick's 

 view that fossils of different strata, seemingly very distinct, were 

 separate creations and not variations by descent. Of course, it is the 

 innumerable intermediate forms between fossil species, and amongst 

 living creatures, now known, which render the conception of 

 separate creations inconceivable ; to say nothing of the many cultivated 

 forms of plants and domestic animals, illustrating modifications by 

 descent. 



The idea of plants changing their structure and form, thereby 

 giving rise to new species, was by no means new, as the following 

 short extracts show ; but when the mind has been long led to believe in 

 one special view, which is taken for granted as true, any other does 

 not recommend itself all at once. Hence neither Humboldt nor 

 Geiesbach saw that the natural inference from their observations led 

 directly to the idea of evolution. 



Even in the sixteenth century Bacon recommended experiments to 

 test the "transmutation of species": "We shall do well to take 

 marsh-herbs and plant. them upon the tops of hills, and such plants as 

 require moisture upon sandy and very dry ground — as, for example, 

 marsh-mallows and sedge upon hills; so, contrariwise, plant bushes, 

 heath, ling, brakes upon .a wet and marshy ground." * 



We read in Humboldt's Cosmos f " The physical description of 

 the globe teaches us that vegetation everywhere presents numerically 

 constant relations in the development of its forms and types; that in 

 the same climates, the species which are wanting in one country are 

 replaced in a neighbouring one by other species of the same family; 

 and this law of substitution seems to depend upon some inherent 

 mysteries of the organism considered with reference to its origin. . . . 

 It might be said, in accordance with a beautiful expression of 

 Lavoisiee, that the ancient marvel of the myth of Prometheus 

 wag incessantly renewed before our eyes." Prometheus formed men 

 of clay and animated them by means of fire brought down from 

 heaven. 



Geiesbach, in his Vegetation de Globe (1877), | observes: "The 

 repetition of analogous forms produced independently of the geographical 

 position would accord with the idea that the constitution of a plant 

 is only the result of the physical conditions which have presided at its 

 birth." Again, he says : " The centres of vegetation depend upon their 

 geographical position, and the organizing forces possess the faculty of 

 always adapting the results to the physical conditions of life — without, 

 however, our knowing the processes by which this force works, because 



* Centwy, vi, t 1844, Bohn's ed. p. 43. X I. pp. 9, 10. 



