Absence from home and consequent idleness are the causes that I have not sooner thanked you for your very kind present of your Lectures. (161/1. "On the Germs and Vestiges of Disease," (London) 1861.) Your reasoning seems quite satisfactory (though the subject is rather beyond my limit of thought and knowledge) on the V.M.F. not being "a given quantity." (161/2. "It has been too common to consider the force exhibited in the operations of life (the V.M.F.) as a given quantity, to which no accessions can be made, but which is apportioned to each living being in quantity sufficient for its necessities, according to some hidden law" (op. cit., page 41.) And I can see that the conditions of life must play a most important part in allowing this quantity to increase, as in the budding of a tree, etc. How far these conditions act on "the forms of organic life" (page 46) I do not see clearly. In fact, no part of my subject has so completely puzzled me as to determine what effect to attribute to (what I vaguely call) the direct action of the conditions of life. I shall before long come to this subject, and must endeavour to come to some conclusion when I have got the mass of collected facts in some sort of order in my mind. My present impression is that I have underrated this action in the "Origin." I have no doubt when I go through your volume I shall find other points of interest and value to me. I have already stumbled on one case (about which I want to consult Mr. Paget)--namely, on the re-growth of supernumerary digits. (161/3. See Letters 178, 270.) You refer to "White on Regeneration, etc., 1785." I have been to the libraries of the Royal and the Linnean Societies, and to the British Museum, where the librarians got out your volume and made a special hunt, and could discover no trace of such a book. Will you grant me the favour of giving me any clue, where I could see the book? Have you it? if so, and the case is given briefly, would you have the great kindness to copy it? I much want to know all particulars. One case has been given me, but with hardly minute enough details, of a supernumerary little finger which has already been twice cut off, and now the operation will soon have to be done for the third time. I am extremely much obliged for the genealogical table; the fact of the two cousins not, as far as yet appears, transmitting the peculiarity is extraordinary, and must be given by me.
LETTER 162. TO C. LYELL. [February 17th, 1863.]
The same post that brought the enclosed brought Dana's pamphlet on the same subject. (162/1. The pamphlet referred to was published in "Silliman's Journal," Volume XXV., 1863, pages 65 and 71, also in the "Annals and Magazine of Natural History," Volume XI., pages 207-14, 1863: "On the Higher Subdivisions in the Classification of Mammals." In this paper Dana maintains the view that "Man's title to a position by himself, separate from the other mammals in classification, appears to be fixed on structural as well as physical grounds" (page 210). His description is as follows:--
I. ARCHONTIA (vel DIPODA) Man (alone).
II. MEGASTHENA. III. MICROSTHENA. Quadrumana. Cheiroptera. Carnivora. Insectivora. Herbivora. Rodentia. Mutilata. Bruta (Edentata).
IV. OOTICOIDEA. Marsupialia. Monotremata.)
The whole seems to me utterly wild. If there had not been the foregone wish to separate men, I can never believe that Dana or any one would have relied on so small a distinction as grown man not using fore-limbs for locomotion, seeing that monkeys use their limbs in all other respects for the same purpose as man. To carry on analogous principles (for they are not identical, in crustacea the cephalic limbs are brought close to mouth) from crustacea to the classification of mammals seems to me madness. Who would dream of making a fundamental distinction in birds, from fore-limbs not being used at all in [some] birds, or used as fins in the penguin, and for flight in other birds?
I get on slowly with your grand work, for I am overwhelmed with odds and ends and letters.