[56] My observations rest on the fine specimen of this plant preserved in the British Museum. Dr. Harvey, however, says, "The growth of the trunk in Kingia is very slow, and a specimen about ten feet high may probably be some hundreds of years old." Report of Dubl. Univ. Zool. and Bot. Assoc. for Feb. 25, 1857. See the note infra on page 188.
[57] Gaudichaud: Recherches Gén. sur l'Organographie, p. 129.
[58] On the development of Loranthus, &c. Linn. Tr. xviii p. 71, (abridged).
[59] "Each and every plant is at first a cell."—"New cells can never be formed externally to, but only within, other cells already formed." (A. Braun, on the Veg. Indiv.)
"The process of the propagation of cells, by the formation of new cells in their interior, is an universal law in the vegetable kingdom." (Schleiden; Grundzüge).
"Cell-formation in plants takes place only in the cavities of older cells." (Mohl, on the Veg. Cell)
[60] See Von Martius, on the Brazilian Locusts.
[61] The origin of coral-stocks is minutely described by Ehrenberg, in the Abhandl. for 1832, where he makes the following remarks:—"The coral mass is neither a mere structure composed of many animals arbitrarily conjoined, as Ellis supposed; nor one single animal with many heads, or with simple furcations, as Cavolini maintained; nor a vegetable stem with animal flowers, as Linnæus expressed it; it is a body of families, a living tree of consanguinity; the single animals belonging to it, and continually developing upon the primary ancestor, are entirely isolated within themselves, and capable of complete independence, although unable to achieve it."
[62] This is not quite in accord with Lamouroux's account; but it is more consistent with what we know of polype-growth.
[63] We lack precise data on which to found conclusions as to the actual rate of growth of many animals. Sir John Dalyell's famous Actinia, now in the possession of Dr. Fleming, affords us a proof that the Zoophytes are long-lived, and slow in attaining maturity. It will be readily seen, however, that the argument in the text does not depend on the actual period evolved. The lapse of a period of time, no matter how long, is the only essential point.