The Principles of Biology

AUTHOR OF "social STATICS," "THE PRINCIPLES OF PSYCHOLOGY,'* " ESSAYS : SCIENTIFIC, POLITICAL, AND SPECULATIVE," " FIRST PRINCIPLES," ETC. VOL. I. WILLIAMS AND NOEGATE, 14, HENRIETTA STREET, COYENT GARDEN, LONDON; AND 20, SOUTH FREDERICK STREET, EDINBURGH. The right of Translation is reserved. JOHN OniLDS AND SON. TKINTERS. PEEFACE. The aim of tMs work is to set forth the genei^al truths of Biology, as illustrative of, and as interpreted by, the laws of Evolution : the special truths being introduced only so fai' as is needful for elucidation of the general truths. For aid in executing it, I owe many thanks to Prof. Huxley and Dr Hooker. They have supplied me with information where my own was deficient ; and in looking through the proof-^^heets, have pointed out errors of detail into which I had fallen. By having kindly rendered me this valuable assistance, they must not, however, be held committed to any of the enunciated doctrines that are not among the recognized truths of Biology. The successive instalments which compose this volume, were issued to the subscribers at the following dates : — No. 7 (pp. 1—80) in January, 1863; No. 8 (pp. 81—160) in April, 1863; No. 9 (pp. 161—240) in July, 1863; No. 10 (pp. 241—320) in January, 1864; No. 11 (pp. 321—400) in May, 1864; and No. 12 (pp. 401—476) in October, 1864. London, Sejptenfiber 29th, 1864. f \l CONTENTS OF VOL L PAET I.— THE DATA OF BIOLOGY. CHAP. PAGE I. — OEGAJ^^IC MATTER " . . . . , . . . 3 II. — THE ACTIONS OF EORCES ON ORGANIC MATTER . . 25 III. — THE RE-ACTIONS OF ORGANIC MATTER ON FORCES 42 IV. — PROXIMATE DEFINITION OF LIFE . . . . 59 V. — THE CORRESPONDENCE BETWEEN LIFE AND ITS CIR- CUMSTANCES . . . . . . . . 72 VI. — THE DEGREE OF LIFE VARIES AS THE DEGREE OF CORRESPONDENCE . . . . . . 82 VII. — THE SCOPE OF BIOLOGY . . . . . . 94 PAET II.— THE INDUCTIONS OF BIOLOGY. I. — GROWTH II.…