4 
simply an heritage. In view of the recent statements of Mr. Balbiani, 
v pecting the androgynous condition of the Aphis, a question presents 
itself for discussion ; namely, whether the polar cells of the pseudovum 
can be interpreted as representing male as well as female elements. As far 
as present observations go, this hypothesis is negatived by every writer, 
since each of them expressly states that nothing bearing the least resem- 
blance to sperm-cells or spermatozoa could be seen. The several descrip- 
tions of the germ-mass or sexual gland point distinctly to its ovarian 
character, though considerable diversity of opinion is shown respecting the 
exact analogies of the germ-mass itself, and of the reproductive bodies 
yielded by it. Histologically the germs correspond with pseudova, and 
their development without fertilisation (except indeed this fertilisation be 
supposed to have been already effected in the insect egg) places the phe- 
nomena on the specialfooting of a parthenogenetic process. A particular in- 
terest therefore attaches itself to the question whether there be a limit (and 
what limit) to this procreating power, and under what conditions is it ex- 
hausted ? Do the phenomena resolve themselves into an act of mere 
growth capable of being indefinitely prolonged ? The doctrine of alter- 
nate generation expressly limits the act of propagation to the production 
of a series of individuals intervening between two generations of sexually 
mature individuals. The notion of genesis also necessarily implies speciality 
of power and function, however interrupted by transference from one nurse 
to another, and can scarcely be reduced to mere repetitive multiplication of 
immature animals. The fact remains that an insect egg supplies in sepa- 
rate portions materials from which new individuals are formed, and materials 
which continue the functions of reproduction — ultimately, therefore, many 
mature individuals must result from this compound egg. In the plan of 
creation, the multiplication of individuals and continuity of species is 
equally effective, whether each separate egg becomes a mature individual 
or a large egg subdivides itself into portions which successively produce a 
progeny. The genetic relation is equally preserved, and it is a secon- 
dary question whether each individual must of necessity be a 
progenitor by its own act, or simply participate in a particular 
phase of genetic phenomena already initiated. Reproduction 
must always remain a specialised function distinguished from the more 
general act of growth, and the heritage of procreating power is equally 
distinct from the nutritive life and vitality of a creature capable 
of an individual and independent existence, though incapable of attaining 
the perfect form ; the final phase of creatures that pass through metamor- 
phoses more or less perfect until they attain the complete type, is usually 
the performance of genetic functions. But we see in a multitude of 
instances that metamorphosis belongs rather to the particular life of the 
individual than to any purpose of continuing species ; it is at least, as we 
see in the case before us, no necessary condition to the perfect fulfilment 
of the gestating function in immature creatures, such us our larva- perform. 
