[104] Unsere Körperform, Leipzig, 1874.
[105] No such point of inflection appears in the curve of weight according to C. M. Jackson’s data (On the Prenatal Growth of the Human Body, etc., Amer. Journ. of Anat. IX, 1009, pp. 126, 156), nor in those quoted by him from Ahlfeld, Fehling and others. But it is plain that the very rapid increase of the monthly weights, approximately in the ratio of the cubes of the corresponding lengths, would tend to conceal any such breach of continuity, unless it happened to be very marked indeed. Moreover in the case of Jackson’s data (and probably also in the others) the actual age of the embryos was not determined, but was estimated from their lengths. The following is Jackson’s estimate of average weights at intervals of a lunar month:
| Months | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Wt in gms. | ·0 | ·04 | 3 | 36 | 120 | 330 | 600 | 1000 | 1500 | 2200 | 3200 |
[106] G. Kraus (after Wallich-Martius), Ann. du Jardin bot. de Buitenzorg, XII, 1, 1894, p. 210. Cf. W. Ostwald, Zeitliche Eigenschaften, etc. p. 56.
[107] Cf. Chodat, R., et Monnier, A., Sur la courbe de croissance des végétaux, Bull. Herb. Boissier (2), V, pp. 615, 616, 1905.
[108] Cf. Fr. Boas, Growth of Toronto Children, Rep. of U.S. Comm. of Education, 1896–7, pp. 1541–1599, 1898; Boas and Clark Wissler, Statistics of Growth, Education Rep. 1904, pp. 25–132, 1906; H. P. Bowditch, Rep. Mass. State Board of Health, 1877; K. Pearson, On the Magnitude of certain coefficients of Correlation in Man, Pr. R. S. LXVI, 1900.
[109] l.c. p. 42, and other papers there quoted.
[110] See, for an admirable résumé of facts, Wolfgang Ostwald, Ueber die Zeitliche Eigenschaften der Entwickelungsvorgänge (71 pp.), Leipzig, 1908 (Roux’s Vorträge, 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 (Vitalität), pp. 85–87.
[111] Cf. St Loup, Vitesse de croissance chez les Souris, Bull. Soc. Zool. Fr. XVIII, 242, 1893; Robertson, Arch. f. Entwickelungsmech. XXV, p. 587, 1908; Donaldson. Boas Memorial Volume, New York, 1906.
[112] Luciani e Lo Monaco, Arch. Ital. de Biologie, XXVII, p. 340, 1897.