100 REPORT— 1876. 



BIOLOGY. 



Address by Alfred Russel Waixace, F.R.G.S., F.L.S., President of the 



Section. 



The range of subjects comprehended within this Section is so wide, and my 

 own acquaintance with them so imperfect, that it is not in my power to lay 

 before you any general outline of the recent progress of the biologisal sciences. 

 Neither do I feel competent to give you a summary of the present status 

 of any one of the great divisions of our science, such as Anatom}^, Physiology, 

 Embryology, Histology, Classification, or Evolution — Philology, Ethnology, or 

 Prehistoric Archaeology ; but there are fortunately several outlying and more or 

 less neglected subjects to which I have for some time had my attention directed, 

 and which I hope will fui-nish matter for a few observations of some interest to 

 biologists, and be at the same time not unintelligible to the less scientific members 

 of the Association who may honour us with their presence. 



The subjects I first propose to consider have no general name, and are not easily 

 grouped under a single descriptive heading ; but they may be compared with 

 that recent development of a sister science which has been termed Surface- 

 geology or Earth-sculpture. In the older geological works we learnt much about 

 strata, and rocks, and fos?ils, their superposition, contortions, chemical constitution, 

 and affinities, with some general notions of how they were formed in the remote 

 past; but we often came to the end of the volume no whit the wiser as to how 

 and why the surface of the earth came to be so wonderfully and bcauti- 

 fullv diversified ; we were not told why some mountains are rounded 

 and others precipitous ; why some valleys are wide and open, others narrow and 

 rocky; why rivers so often pierce through mountain-chains; why mountain 

 lakes are often so enormously deep; whence came the gravel, and drift, and 

 erratic blocks so strangely spread over wide areas while totally absent from 

 other areas equally extensive. So long as these questions were almost ignored, 

 geology could hardly claim to be a complete science, because, while professing to 

 explain how the crust of the earth came to be what it is, it gave no intelligible 

 account of the varied phenomena presented by its surface. But of late years these 

 surface-phenomena have been assiduously studied ; the marvellous effects of denu- 

 dation and glacial action in giving the final touches to the actual contour of the 

 earth's surface, and their relation to climatic changes and the antiquity of man, 

 have been clearly traced, thus investing geology with a new and popular interest, 

 and at the same time elucidating many of the phenomena presented in the older 

 formations. 



Now just as a surface-geology was required to complete that science, so a surface- 

 biology was wanted to make the science of living things more complete and more 

 generally interesting, by applying the results arrived at by special workers to the in- 

 terpretation of those external and prominent features whose endless variety and beauty 

 constitute the charm which attracts us to the contemplation or to the study of nature. 

 The descriptive zoologist, for example, gives us the external characters of ani- 

 mals ; the anatomist studies their internal structure ; the histolog'st makes known 

 to us the nature of their component tissues; the embryologist patiently watches 

 the progi'ess of their development ; the systematist groups them into classes and 

 orders, families, genera, and species ; while the field-naturalist studies for us their 

 food and habits and general economy. But till quite recently none of these earnest 

 students, nor all of them combined, could answer satisfactorily, or even attempted 

 to answer, many of the simplest questions concerning the external characters and 

 general relations of animals and plants. Why are fiowers so wonderfully varied 

 in form and colour? what causes the Arctic fox and the ptarmigan to turn white 

 in winter ? why are there no elephants in America and no deer in Auslriilia? 

 why are closely allied species rarely found together? why are male animals so 

 frequenth' bright-coloured? why are extinct animals so oltcu larger tjian tho.se 

 which are now living? what has led to the production of the gorgeous train of 

 the peacock and of the two kinds of flower in the primrose ? The solution of 



