h
Medical Journal,' April, 1863.

[901] This term is used by Dr. E. Montgomery ('On the Formation of
so-called Cells in Animal Bodies,' 1867, p. 42), who denies that cells are
derived from other cells by a process of growth, but believes that they
originate through certain chemical changes.

[902] Prof. Huxley has called my attention to the views of Buffon and
Bonnet. The former ('Hist. Nat. Gen.,' edit. of 1749, tom. ii. pp. 54, 62,
329, 333, 420, 425) supposes that organic molecules exist in the food
consumed by every living creature; and that these molecules are analogous
in nature with the various organs by which they are absorbed. When the
organs thus become fully developed, the molecules being no longer required
collect and form buds or the sexual elements. If Buffon had assumed that
his organic molecules had been formed by each separate unit throughout the
body, his view and mine would have been closely similar.

Bonnet ('Oeuvres d'Hist. Nat.,' tom. v., part i., 1781, 4to edit., p. 334)
speaks of the limbs having germs adapted for the reparation of all possible
losses; but whether these germs are supposed to be the same with those
within the buds and sexual organs is not clear. His famous but now exploded
theory of _emboitement_ implies that perfect germs are included within
germs in endless succession, pre-formed and ready for all succeeding
generations. According to my view, the germs or gemmules of each separate
part were not originally pre-formed, but are continually produced at all
ages during each generation, with some handed down from preceding
generations.

Prof. Owen remarks ('Parthenogenesis,' 1849, pp. 5-8), "Not all the progeny
of the primary impregnated germ-cell are required for the formation of the
body in all animals: certain of the derivative germ-cells may remain
unchanged and become included in that body which has been composed of their
metamorphosed and diversely combined or confluent brethren: so included,
any derivative germ-cell, or the nucleus of such, may commence and repeat
the same processes of growth by imbibition, and of propagation by
spontaneous fission, as those to which itself owed its origin;" &c. By the
agency of these germ-cells Prof. Owen accounts for parthenogenesis, for
propagation by self-division during successive generations, and for the
repairs of injuries. His view agrees with mine in the assumed transmission
and multiplication of his germ-cells, but differs fundamen