2 INTRODUCTION. 



abstruse branch of the science is merely alluded to here in, 

 passing. 



If we consider a portion of the animal body with respect to 

 its form, size, relative position, or structure, we are said to 

 consider it anatomically ; but should we inquire into the use or 

 function of such portion, or seek to know the changes undergone 

 by it while in a living condition, then we are investigating it 

 l^hysiologically. Such is a general distinction between the 

 sciences of Anatomy and Physiology ; but it will readily be seen 

 that they are to a great extent bound up in one another, since 

 both the sciences must lend their aid to afford a complete 

 description of any given organ or part. The branch treating 

 solely of structure and form is termed Morphology. Histology, 

 otherwise called General or Minute Anatomy, treats of the intimate 

 structure of the tissues or materials of which the various parts of 

 the body are composed. As the tissues present certain character- 

 istics invisible to the naked eye, the microscope is largely employed 

 by the histologist in his investigations. Embryology, from an 

 anatomical point of view, is a science considering the various 

 appearances presented by an animal after each of the many 

 successive stages of its development, — from when it first appears 

 as a mere speck of vitality until it has acquired the general 

 characteristics of a perfect animal. 



Anatomy, in all the above-mentioned branches, deals only with 

 normal or healthy material ; but should such material be in a 

 diseased condition, the consideration of the changes it has conse- 

 quently undergone is termed Morbid Anatomy. Surgical Anatomy 

 embraces the description and investigation of such parts of the 

 body as are most liable to be involved in surgical operations. 

 The surgeon, by a competent knowledge of this branch of the 

 subject, is enabled to operate with the maximum of safety and 

 expedition, together with the minimum of pain and inconvenience 

 to the patient. 



Anatomy in either of its aspects may be descriptive or 

 practical. In the former, the student relies on books, diagrams, 

 lectures, &c., for his information ; in the latter, he verifies descrip- 

 tions by actual dissection and demonstration of the various 

 structures in question. 



Veterinary Anatomy, in the full sense of the word, includes the 

 anatomy of all the domesticated animals, and is, therefore, a 

 branch of the comparative science, and the animal usually 



