In the assumed process the correcting force of the Lamarckian drill-sergeant is always at hand, as it superintends the construction of tissues and parts, and I doubt if even Professor Thomson will here interpose the difficulty of “correlation with useful characters,” for the only important functions which are invoked as the invariable antecedent of these structures are the elementary habits of walking, climbing or grasping objects in certain different ways, and without these habits or functions there would be neither lemur, monkey nor man to interest the mind of a biologist from Mars. As I am desirous of condensing such replies as I can make to certain opinions of opponents and objections, I will remind the reader that Professor Bateson in the _Jubilee Volume_ of 1909, pp. 100, 101, uses a metaphor to illustrate his view that among the facts of nature we meet certain definite structures and patterns in which we ought not, if desiring rightly to interpret them, to expect to find _purposefulness_. He says: “Such things are, as often as not, I suspect rather of the nature of tool-marks, mere incidents of manufacture, benefiting their possessor not more than the wire-marks in a sheet of paper, or the ribbing on the bottom of an oriental plate renders these objects more attractive in our eyes.” Metaphors are both indispensable and delightful, they are the very salt of scientific and other sober writings, but they have a rather “slim” way of betraying their employers. They express at times the truth too well, and at others when vague and inaccurate lead the reader right astray. Thinking of this metaphor of tool marks I was in a modern church the other day and saw just before me a stone pillar the pediment of which was marked with oblique parallel marks of a mason’s tool. Here then there were marks left by a human hand at some date or other and by means of some tool or other. I know one may not reason by an analogy from inorganic to organic phenomena in which the push and force of life is in full blast, and that inheritance in the former is ruled out; but, taking the metaphor seriously, you have to account for the appearance of the ribbing of paper and the mason’s marks on the stone. To call them “by-products” or “tool marks” or _obiter facta_, or by any suggestive name, does not advance the reply to the question, “Whence came this great multitude?” If I were unwary enough to be here trying to attack Selection and to respond to the invitation of the more learned arachnida to walk into his parlour with a scheme of organic evolution for him to demolish at his leisure, I should have to enter upon the question of adaptation, specific difference and perhaps other great disputed doctrines. But, knowing my own limits, and desiring to keep to the self-imposed limits of the title of this book, I again plead that I am here contending, as all through it, for the origin of initial modifications by use and habit, and for nothing else. No