CHAPTER VII

.--THE PROGRESS OF ICHTHYOLOGY. 419

Period of Unsystematic Knowledge. 420 Period of Erudition. 421 Period of Accumulation of Materials.--Exotic Collections. 422 Epoch of the Fixation of Characters.--Ray and Willoughby. 422 Improvement of the System.--Artedi. 423 Separation of the Artificial and Natural Methods in Ichthyology. 426

_ORGANICAL SCIENCES._

## BOOK XVII.

HISTORY OF PHYSIOLOGY AND COMPARATIVE ANATOMY.

Introduction. 435 {16}

## CHAPTER I .--DISCOVERY OF THE ORGANS OF VOLUNTARY MOTION.

_Sect._ 1. Knowledge of Galen and his Predecessors. 438 _Sect._ 2. Recognition of Final Causes in Physiology.--Galen. 442

##