127 Cf. chap. xvii, p. 739.
128 ãô ...I marked in the same manner as the Vine, young Honeysuckle shoots, etc....; and I found in them all a gradual scale of unequal extensions, those parts extending most which were tenderest,ã Vegetable Staticks, Exp. cxxiii.
129 From Sachs, Textbook of Botany, 1882, p. 820.
130 Variation and Differentiation in Ceratophyllum, Carnegie Inst. Publications, No. 58, Washington, 1907.
131 Cf. LûÊmmel, Ueber periodische Variationen in Organismen, Biol. Centralbl. XXII, pp. 368ã376, 1903.
132 Herein lies the easy answer to a contention frequently raised by Bergson, and to which he ascribes great importance, that ãa mere variation of size is one thing, and a change of form is another.ã Thus he considers ãa change in the form of leavesã to constitute ãa profound morphological difference.ã Creative Evolution, p. 71.
133 I do not say that the assumption that these two groups of earwigs were of different ages is altogether an easy one; for of course, even in an insect whose metamorphosis is so simple as the earwigãs, consisting only in the acquisition of wings or wing-cases, we usually take it for granted that growth proceeds no more after the final stage, or ãadult formã is attained, and further that this adult form is attained at an apôÙproxôÙiôÙmateôÙly constant age, and constant magnitude. But even if we are not permitted to think that the earwig may have grown, or moulted, after once the elytra were produced, it seems to me far from impossible, and far from unlikely, that prior to the appearance of the elytra one more stage of growth, or one more moult took place in some cases than in others: for the number of moults is known to be variable in many species of Orthoptera. Unfortunately Bateson tells us nothing about the sizes or total lengths of his earwigs; but his figures suggest that it was bigger earwigs that had the longer tails; and that the rate of growth of the tails had had a certain definite ratio to that of the bodies, but not necessarily a simple ratio of equality.
134 Jackson, C. M., J. of Exp. Zool. XIX, 1915, p. 99; cf. also Hans Aron, Unters. û¥ber die Beeinflû¥ssung der Wachstum durch die ErnûÊhrung, Berl. klin. Wochenbl. LI, pp. 972ã977, 1913, etc.
136 Rûˋaumur: Lãart de faire ûˋclore et ûˋlever en toute saison des oiseaux domestiques, foit par le moyen de la chaleur du fumier, Paris, 1749.