ORIGIN AND TRANSFORMATION OP ANIMALS. 
243 
destined for development outside the maternal bosom^ they 
have received an envelope of greater or less solidity, according 
to the protection against accidents Mhich they are likely to 
require in the external world?.But if these repro¬ 
ductive bodies are hucls^ not eggs, it follows that development 
without male intervention belongs to the phenomena which 
we have been studying, and that we have thus wot parthenoge¬ 
nesis, but geneagenesis.^^ 
Regarding no object as a veritable egg which does not 
possess the Purkinje vesicle and the Wagner spot, M. Quatre- 
fages considers that cases of parthenogenesis will be greatly 
diminished, but he is convinced they will not be entirely 
obliterated from the book of science. He admits, without, 
as he says, going as far as Huxley, Owen, and Lubbock, that 
there exist ‘^intermediaries” between eggs and buds, but, 
after all reservations, “parthenogenesis is not,inhis eyes, a con¬ 
stant fact.^^ He admits that there exist “ true females, laying 
veritable eggs, which develop themselves without male inter¬ 
vention in any way whatever;’^ but he thinks these phenomena 
are supposed to be much more frequent than is really the 
case, and that reproduction by females only tends to exhaust 
itself, and that “ always, the intervention of the male, recur¬ 
ring at a given moment, as a necessary element in the perpe¬ 
tuity of species, is evidently one of the great laws of nature.” 
The father is thus “ as necessary as the mother for the inde¬ 
finite duration of species, and the point of departure for a 
cycle of generations is not only an egg, but a fertilised egg.” 
Pathenogenesis is, then, “ only a particular case oigeneagenesisP 
We cannot now follow M.Quatrefages through the vegetable 
kingdom in which he pursues his theme, but we may observe 
that philosophers, who require every step in an inductive pro¬ 
cess of reasoning to be strictly proved, will hesitate before 
they affirm with him that “ a father and a mother—that, is a 
male and a female—such is the origin of every living being.” 
They will likewise prefer a frank confession of ignorance as 
to how and why the characteristics of individuals descend to 
their posterity, to the assertion that “ an essence proper to the 
character of each beingis received from its ancestors and 
transmitted to its posterity. All, however, will allow that 
M. Quatrefages has produced an admirably written and 
learned work, which supplies the profoundest naturalist with 
deep matter for investigation and thought, while, from the 
elegance of the language and the clearance of the style, it is 
admirably adapted for popular use. 
