663 There is a paper on the mathôÙeôÙmatôÙiôÙcal study of organic forms and organic processes by the learned and celebrated Gustav Theodor Fechner, which I have only lately read, but which would have been of no little use and help to our argument had I known it before. (Ueber die mathematische Behandlung organischer Gestalten und Processe, Berichte d. k. sûÊchs. Gesellsch., Math.-phys. Cl., Leipzig, 1849, pp. 50〓64.) Fechner〙s treatment is more purely mathôÙeôÙmatôÙiôÙcal and less physical in its scope and bearing than ours, and his paper is but a short one; but the conclusions to which he is led differ little from our own. Let me quote a single sentence which, together with its context, runs precisely on the lines of the discussion with which this chapter of ours began. 〜So ist also die mathematische Bestimmbarkeit im Gebiete des Organischen ganz eben so gut vorhanden als in dem des Unorganischen, und in letzterem eben solchen oder ûÊquivalenten BeschrûÊnkungen unterworfen als in ersterem; und nur sofern die unorganischen Formen und das unorganische Geschehen sich einer einfacheren Gesetzlichkeit mehr nûÊhern als die organischen, kann die Approximation im unorganischen Gebiet leichter und weiter getrieben werden als im organischen.

110 See, for an admirable rûˋsumûˋ of facts, Wolfgang Ostwald, Ueber die Zeitliche Eigenschaften der EntôÙwickeôÙlungsôÙvorôÙgûÊnge (71 pp.), Leipzig, 1908 (Roux〙s VortrûÊge, Heft V): to which work I am much indebted. A long list of observations on the growth-rate of various animals is also given by H. Przibram, Exp. Zoologie, 1913, pt. IV (VitalitûÊt), pp. 85〓87.

117 This phenomenon, of incrementum inequale, as opposed to incrementum in universum, was most carefully studied by Haller: 〜Incrementum inequale multis modis fit, ut aliae partes corporis aliis celerius increscant. Diximus hepar minus fieri, majorem pulmonem, minimum thymum, etc.〝 (Elem. VIII (2), p. 34).