CONTENTS.

CHAPTER I. Page

Introductory Remarks[1]

CHAPTER II.

Fact of Variation[7]
As a matter of experience [8]
As probable from analogy [10]

CHAPTER III.

Causes of Variation[19]
§ 1. Climatal causes generally (whether dependent
upon latitude or upon altitude) [23]
§ 2. Temporary heat or cold, of an unusual degree [42]
§ 3. Nature of the country, and of the soil [46]
§ 4. Isolation; and exposure to a stormy atmosphere [70]

CHAPTER IV.

Organs and Characters of Variation[95]

CHAPTER V.