286 BULLETIN OF THE BUSSEY INSTITUTION. | 
No. 12.— Applied Zodlogy. | The Importance of its Study to 
the Practical ‘Agriculturist. By D. D. SuapE, M.D., 
Professor of Appled Zodlogy. 
ZooOLoGy is that department of natural history which imvestigates 
and teaches the nature and properties of animals in general. Applied 
Zodlogy is this department restricted to those animals that man has 
especially subjected to his dominion, and which are commonly known 
as domesticated animals. In its broadest sense Applied Zodlogy 
includes all that pertains to these animals in health and disease. It is 
the study of their anatomy, physiology, pathology, and therapeutics. 
Anatomy teaches us the form, structure, and connection of every por- 
tion of the body, and its study in the widest sense exacts a previous 
knowledge of inorganic substances and the chemical laws which gov- 
ern them. Physiology is the science which treats of the functions 
presented by organized bodies, animal or vegetable, — of the growth, 
chemical changes, and reproduction of these bodies. It requires an 
acquaintance with their mechanical, structural, and chemical composi- 
tion, —in other words, with their anatomy. Anatomy is, then, the 
groundwork of physiology. A knowledge of these naturally leads 
to the study of the diseases of organic bodies; to pathology, as it 
is termed; and this in turn to therapeutics, or the cure of these 
diseases. 
But why, it may be asked, is a knowledge of anatomy essentially im- 
portant to the practical farmer? Because the laws governing the vital 
functions of animals —that is, animal physiology —cannot be prop- 
erly understood without it. Nutrition, for example, comprehends not 
only all that relates to the substances which enter into the animal 
body, their different forms, quantities, and qualities, but also the pro- 
cesses of digestion and absorption, the circulation of the blood, the 
phenomena connected with respiration, and with the various excre- 
tions and secretions. In the feeding of stock, whether he has in view 
the growth and development of muscle, or the increase of fat, or 
the production of butter, the intelligent agriculturist should be ae- 
quainted with the physiological laws which govern these conditions, in 
order that he may attain the best results. 
