1 Jury, 1899.] QUEENSLAND AGRICULTURAL JOURNAL. 17 
as to the second, it may be argued that such migration of spermatozoa from the 
vagina into the ovary has never been traced nor proved, and if it had taken 
place the effects would have been that more ovules would have come to maturity 
at the same time; the third explanation can scarcely be accepted, because 
according to some physiologists there is no true circulation between footus and 
mother, as had been supposed to exist, and that the foetus grows by osmosis. 
Dr. Carpenter says :—‘ Some of these cases appear referable to the strong 
mental impression left by the first male parent upon the female; but there are 
others which seem to render it more likely that the blood of the female has 
imbibed from the foetus through the placental circulation some of the attributes 
which the latter has derived from its male parent, and that the female may 
communicate these with those proper to herself to the subsequent offspring of 
a different male parentage.” Professor Agassiz seems to be inclined to hold 
the secondly mentioned explanation. He has shown that turtles begin to 
copulate at the age of seven years, but do not lay until. they are eleven years 
old; they copulate twice each year for four years before the eggs are fully 
matured. Upon opening large numbers of young freshwater turtle of the 
species Chrysemys, it was ascertained that up to their seventh year the ovary 
contained only eggs of very small size, not distinguishable into sets; but 
with every succeeding year there appears in that organ a larger and larger set 
of eggs, each set made up of the usual average number of eggs which this 
species lays, so that specimens eleven years old for the first time contain mature 
eggs ready to be laid in the spring. 
From the observations made by Agassiz it appears that the first copulation 
coincides with a new development of the eggs, in consequence of which a number 
of them, equal to that which the species lays, acquire a larger size and go on 
growing for four successive years before they are laid; while a new set is started 
every year at the period of copulation in the spring, enabling this species to lay 
annually from 5 to 7 eggs after it has reached its eleventh year. 
After a careful examination of all the known ‘facts bearing upon this 
interesting subject, Agassiz became satisfied that the first copulation only deter- 
mines the further growth of a certain number of eggs, which require a series of 
successive fecundations to undergo their final development, and that in turtles a 
repetition of the act, twice every year for four successive years, is necessary to 
determine the final development of a new individual, which may be accomplished 
in other animals by a single copulation. 
In a subsequent lecture, in speaking of the influence of previous impreg- 
nation upon offspring at alater period, Agassiz says:—“ It therefore shows what I 
have satisfied myself to be the truth among other animals by numerous experi- 
ments: that the act of fecundation is not an act which is limited in its effects, 
but that it is an act which affects the whole system, the sexual system especially, 
and in the sexual system the ovary to be impregnated hereafter is so modified 
by the first act that later impregnations do not efface that first impression.” 
Darwin, in his “ Animals and Plants under Domestication,” cites a number 
of instances in the vegetable kingdom to show the direct action of the male 
element on the mother form,.and he comes to the conclusion that “ the male 
element not only affects, in accordance with its proper function, the germ, but 
the surrounding tissues of the mother plant.” Further on, Darwin remarks: 
‘The analogy from the direct action of foreign pollen on the ovarium and seed- 
coats of the mother plant strongly supports the belief that the male element acts 
directly on the reproductive organs of the female, wonderful as is this action, 
and not through the intervention of the crossed embryo.” 
Here we have a doctrine of great importance before us. For it is evident 
to every practical breeder that we might economise the services of valuable sires 
if we could place implicit reliance upon its holding good in every species, and 
under all circumstances. In the meantime, these facts may serve as a caution to 
be careful in never allowing a female to be mated with an inferior male, especially 
at the first time, tah 
