Proc. Linn. Soc., 1867-8, p. 57.

It is not enough that females should be produced from the males with red feathers, which should be destitute of red feathers; but these females must have a latent tendency to produce such feathers, otherwise they would cause deterioration in the red head-feathers of their male offspring. Such latent tendency would be shown by their producing the red feathers when old or diseased in their ovaria.

The symbols [male symbol], [female symbol] stand for male and female respectively.

The fifth.

Explained in letter of February 2, 1869. See p. 234.

June, 1867.

"Malay Archipelago."

"Malay Archipelago."

The fifth edition, pp. 150-7.

In the Quarterly Review, April, 1869.