Such an admission, however, ought not to be made without strong evidence being assigned.

The vague and in some respects false analogies, as they have been shown to be by Mr.

Chauncey Wright, which have been advanced in favour of this view, such as the sudden crystallisation of inorganic substances, or the falling of a facetted spheroid from one facet to another, hardly deserve consideration.

One class of facts, however, namely, the sudden appearance of new and distinct forms of life in our geological formations supports at first sight the belief in abrupt development.