On the contrary, structures which are rudimentary in the parent-species, sometimes become partially redeveloped in our domesticated productions.

We see the same process of extermination among our domesticated productions, through the selection of improved forms by man.

We will now consider, as far as we can, the causes of the almost universal variability of our domesticated productions.

According to our experience, abrupt and strongly marked variations occur in our domesticated productions, singly and at rather long intervals of time.

This does not occur, or only in a very slight degree, with our domesticated productions, which have long been exposed to fluctuating conditions.

Mr. Darwin writes: "All our domesticated productions, with the rarest exceptions, vary far more than natural species" ("Plants and Animals," &c., vol.

Nevertheless the law of compensation or balancement, which likewise depends on the economy of growth, apparently has affected to a certain extent our domesticated productions.

With domesticated productions, although their organs sometimes become rudimentary through abortion, we have no reason to suppose that this has ever followed solely from disuse.