histologie

Updated: May 3, 2025

Numerous examples, which might easily be augmented, of such profound differences, are furnished by Leydig's 'Lehrbuch der Histologie. In the Crustacea the ovarian eggs actually sometimes furnish excellent characters for the discrimination of species of the same genus; thus, for example, in one Porcellana of this country they are blackish-green, in a second deep blood-red, and in a third dark yellow; and within the limits of the same order they present considerable differences in size, which, as Van Beneden and Claus have already pointed out, stands in intimate connexion with the subsequent mode of development.

Fritz Muller - Facts and Arguments for Darwin