442 GENERAL ZOOLOGY 



had been forced to study the lower forms. With Vesalius 

 and his contemporaries modern anatomy may be said to have 

 begun. 



Konrad von Gesner (1516-1565), born at Zurich, Switzer- 

 land, had a wide interest in natural history. He was a poor 

 boy, left an orphan, and his early life was one constant strug- 

 gle with poverty. Conquering all difficulties, so great was 

 his enthusiasm for science, he rose to be professor of natural 

 history in his native city. He made collections of animals 

 and plants, and published (15511558) a great History of Ani- 

 mals, in which he described all the animals then known, with 

 statements concerning their structure and habits, some details 

 of their physiology, and their economic importance. This 

 was the first comprehensive work on natural history since 

 the time of Aristotle. 



Zoology of the Seventeenth Century. To William Harvey 

 (1578-1657), an Englishman who studied at Padua under a 

 pupil of Vesalius, we are indebted for the first accurate state- 

 ment of the circulation of the blood in man. Galen had shown 

 the existence of blood in the arteries, and Harvey's professor 

 at Padua had confirmed the existence of the valves in the 

 course of the venous circulation, pointed out by a still earlier 

 investigator ; but it was left to Harvey's painstaking observa- 

 tions to follow the course of the blood from the heart to the 

 lungs, from the lungs back to the heart, and thence all over 

 the body. Harvey's discovery was made in 1614 and pub- 

 lished in 1628, after his return to London, where he practiced 

 as a physician. Like many another discovery in science, it 

 at first aroused hostile criticism. From this period the rise 

 of animal physiology may be dated. Harvey also studied the 

 development of the chick in the egg, arid may be said to be 

 the founder of modern embryology. Of course he did not 

 understand the egg as well as we understand it to-day, since 

 he believed in spontaneous generation. 



