214 Professor E. Forbes' s Lecture on the Relations 



to their examinations, usually in the state of a preserved specimen, 

 and, on discovery of the species being one hitherto unnoticed, give 

 it a name by which it may be remembered by their brother natural- 

 ists to the end of time, or thereabouts, they have attained all their 

 aim, and fulfilled all their ambition. This notion of their duties 

 and offices is a libel. It takes note of only a fragment of their 

 labours. To name and describe are but to enrol an object, with a 

 true spelling and clear definition, in the great dictionary of science. 

 Words in dictionaries are exhibitions of the raw materials out of 

 which literature is made ; and species arranged in zoological and 

 botanical systems are orderly and beautiful displays of the raw mate- 

 rials of natural history science. Words may be wasted, and species 

 misused. But the study of species, which is the basis of all natural 

 history science, does not take note merely of their external or even 

 their internal organisation. It deals also with their relations to con- 

 ditions in time and space. It seeks out the epoch of their first ap- 

 pearance, and traces them through their diffusion under favouring, 

 or limitation and final extinction under unfavourable influence. It 

 searches for the causes inherent to their organisation, by which, of 

 two similar yet not identical creatures, the one has the power to 

 battle with varied and very different forces, to maintain a vitality 

 that braves the duration and complicated arrangements of several 

 successive epochs, and, daring alike the freezing cold of the poles 

 and the feverish warmth of the equator, to spread its individuals 

 over more than half the world. Whilst the other, distinguished, it 

 may be, from its congener by some apparently slight and useless 

 difference, — though the mark be an indelible brand by which nature 

 has stamped that member of her flock, and that only one, — is incapable 

 of assuming protean variations, or of enduring a slight change in the 

 physical conditions under which it first appeared. It enjoys a fleet- 

 ing existence during a short segment of time ; dies out ere it has 

 spread beyond a mere speck on the earth's surface, disappearing 

 never to reappear ; — perchance, if it belonged to some primeval 

 fauna, never to become known to man, with all his research, unless 

 some bony or shelly framework gave consistence to its otherwise 

 perishable substance. 



But so to deal with our subject, so to work at natural history, 

 how can we proceed without the aid of geology ? It is plainly im- 

 possible. From the moment we recognise a consideration of the 

 relation to time and space of species and genus, as an essential ele- 

 ment of a right and full understanding of them, from that moment 

 the naturalist calls in geology to his aid. And how is geology to 

 help him ? The pure geologist, — the inquirer into the earth's phy- 

 sical features at the different stages of its eventful history, and into 

 the probable nature of its internal constitution and the causes of the 

 inequalities of the outline of its crust, — the pure geologist cannot 

 aid him, but, in his turn, rather expects aid from the naturalist. 



