The headings of the chapters describe the facts, and there is no need to enumerate them here. The first and largest group is studied according to a method which is in a measure applied to all the others. Most of them are external or superficial phenomena and accordingly are open to others beside the expert for observation and corroboration, or the reverse. The typical plan adopted is as follows: a large number of related phenomena are chosen, and the more prominent of these are observed and described. Keeping in mind the two plain issues laid down, the origin of initial modifications and their transmission, I have selected the facts because, especially such as those of the hair, they are very simple, of wide distribution in animals well known to us, such as the domestic horse and man, and none are brought forward which any other observer cannot study for himself if he has some anatomical and physiological knowledge, some training and care in recording observations. In most centres of population there are still left a good supply of horses in streets and stables, of preserved specimens in museums and living ones in zoological gardens, and of hairy young men who will hardly refuse a polite request to examine the minute hairs clothing their trunks and limbs. One has to pursue a certain amount of that study which may be called the sister of plant-ecology, that is, animal-ecology or the behaviour of animals at home. The student of these matters, it may be freely admitted, will complain, unless he has some hypothesis or line of thought to follow, that he has been set down in a valley in which the bones are very many and very dry. But, armed or primed with an hypothesis, he may find an affirmative answer to his question “Can these bones live?” Every group of natural phenomena, _without exception_, has some meaning for those who will interpret nature rather than bully and slight her, and whatever anointed king may claim sovereignty over it the humble fact cannot be denied that “whatever phenomenon is, _is_.”[40] Again I would refer to Howes’ inspiring note: “We live by ideas; we advance by a knowledge of the facts; content to discover the meaning of phenomena, since the nature of things will be for ever beyond our grasp.”[41] The facts adduced are simple, have a chance of recurring and are widely distributed among multicellular animals--the botanists and plants can very well take care of themselves. I must once more state that I am attaching to the considered facts a value of a somewhat unusual kind--_their intrinsic unimportance_. For anyone who has had to encounter the skilful dialectics and counter-attacks of a well-equipped neo-Darwinian it is well that he should remember the maxim of Napoleon, “Be vulnerable nowhere.” It is necessary to show evidence for Lamarckian factors in which no degree of selective value, survival-value, can be seen by hostile sharp-shooter while he works in his trench. The