Comments on a letter from Fritz Müller [11839] and particularly on the subject of the disappearance of certain structures in organisms. FM’s explanation deserves serious consideration.

In reply to a query [in Nature 19 (1879): 433] CD reports that vessels full of water were kept on the deck of a ship to discourage rats from gnawing holes in the ship’s water casks.

CD has repeated a test of whether hybrids of the common and Chinese goose are fertile inter se. Reports his success, and comments on its significance for the theory of descent.

Reports information sent by E. Schulte [12254] on the colours of the male Diadema bolina.

Discusses extent to which consciousness came into play in the origin of certain instincts, including sexual display.