organisation, which uses that very mechanism in order to produce fresh organised forms or to develop the existing ones into new shapes (which, however, always result from that purpose and conformably to it).

It is praiseworthy by the aid of comparative anatomy to go through the great creation of organised natures, in order to see whether there may not be in it something similar to a system and also in accordance with the principle of production. For otherwise we should have to be content with the mere principle of judgement (which gives no insight into their production) and, discouraged, to give up all claim to natural insight in this field.

The agreement of so many genera of animals in a certain common schema, which appears to be fundamental not only in the