12 Professor Burdon Sanderson [Jan. 24, 



Animals, the great fact of Evolution, namely, that from the simplest 

 beginning our own organism, with its infinite comj^lication of parts 

 and powers, no less than that of every animal and plant, unfolds the 

 plan of its existence — taken with the observation that that small 

 beginning was, in all excepting the lowest forms, itself derived from 

 two parents, equally from each— is the basis from which his study 

 and knowledge of the world of living beings takes its departure. 

 For on Evolution and Descent the explorer of the forms, distribution 

 and habits of animals and plants has, since the Darwinian epoch, 

 relied with an ever-increasing certainty, and has found in them the 

 explanation of every phenomenon, the solution of every problem 

 relating to the subject of his inquiry. Nor could he wish for a more 

 secure basis. Whatever doubts or misgivings exist in the minds of 

 " non-biologists " in relation to it, may be attributed partly to the 

 association with the doctrine of Evolution of questions which the 

 true naturalist regards as transcendental ; partly to the perversion or 

 weakening of meaning which the term has suffered in consequence of 

 its introduction into the language of common life, and particularly 

 to the habit of applying it to any kind of progress or improvement, 

 anything which from small beginnings gradually increases. But, 

 provided we limit the term to its original sense — the Evolution of 

 a livin^^ being from its germ by a continuous not a gradual process, 

 there is no conception which is more free from doubt either as to 

 its meaning or reality. It is inseparable from that of Life itself, 

 which is but the unfolding of a predestined harmony, of a prearranged 

 consensus and synergy of parts. 



The other branch of Biology, that with which Ludwig's name 

 is associated, deals with the same facts in a different way. While 

 Ontology regards animals and plants as individuals and in relation 

 to other individuals. Physiology considers the processes themselves 

 of which life is a complex. This is the most obvious distinction, 

 but it is subordinate to the fundamental one, namely, that while 

 Ontology has for its basis laws which are in force only in its own 

 province, those of Evolution, Descent, and Adaptation, we Physio- 

 logists, while accepting these as true, found nothing upon them, 

 using them only as guides to discovery, not for the purpose of 

 explanation. Purposive Adaptation, for example, serves as a clue, 

 by which we are constantly guided in our exploration of the tangled 

 labyrinth of vital processes. But when it becomes our business to 

 explain these processes — to say how they are brought about — we 

 refer them not to biological principles of any kind, but to the 

 Universal Laws of Kature. Hence it happens that with reference 

 to each of these processes, our inquiry is rather how it occurs than 

 why it occurs. 



It has been well said that the Natural Sciences are the children 

 of necessity. Just as the other Natural Sciences owed their origin 

 to the necessity of acquiring that control over the forces of Nature 

 without which life would scarcely be worth living, so Physiology 



