| 1884.] The Theory of Sex and Sexual Genesis. 669 
produced by a plant or animal than of bulblets or gemme. 
Moreover, when produced they are better adapted for dispersal, 
in the case of seeds, to suitable situations for their growth; and 
in the case of eggs, may be deposited in favorable situations by 
the producing animal. 
This advantage of genesis by germ-cells over genesis by the 
production of buds, obtains in all the lower grades of organisms 
inwhich the perpetuation of species depends, to a great extent, 
on the production of a large number of offspring. For the 
higher animals, or for all terrestrial animals, there is the further 
consideration that the large buds which they would have to pro- 
duce, and the mode in which they would have to produce them 
in order to keep up the succession in this way, would so encum- 
ber the producing organism as greatly to lessen its powers of 
selfconservation. „As a matter of fact we do not find any terres- 
trial animal reproducing by buds. The highest aquatic animals 
do so are the Tunicata or Ascidians. In these the buds are 
produced from a large stolon, which the medium in which the 
animal, or associated group of animals, is supported, enables it to 
carry with it without any great interference with its self-conserva- 
tive actions, Besides, in the aquatic mode of life the whole body 
may be soft, and that high degree of differentiation of the tissues 
_ “Rot required, at least in all cases, that is required in terrestrial 
_ mals. But all animals and plants, except the lowest, that 
"produce by the formation of buds, also reproduce from germ- 
cells, In such cases, to whatever advantages the former mode 
-~ Senesis has in keeping up the succession, is added the advan- 
"8e, here pointed out, which attends the latter mode. 
The i of Sexual Genesis —Admitting that there is an 
advantage, of the kind above explained, attending genesis by 
Em-<ells, in the perpetuation of species, the further question 
T of what the advantage or need is of the addition to the 
i contents of the germ-cell of the matter of a s 
_ “order that the single mass may be fitted to initiate the develop- 
f ment of a new individual. No doubt a considerable advantage 
a from crossing. But crossing does not always take pie 
fang genesis. Besides, to assign this reason is not to give a 
at explanation. It leaves the physiological difference 
AS eae the two kinds of generative cells to be determined, and 
bea of the formative and developmental processes 
assigned which makes this difference necessary. 
