CHAPTER VI. 



ON PREPARING OBJECTS FOR THE MICROSCOPE. 



The first requisite is to select perfect specimens of the 

 various objects to be mounted. By the term perfect is 

 here to be understood specimens which have not been 

 mutilated nor undergone decomposition. The next re- 

 quisite is to collect the largest and most highly developed 

 specimens. In the lower tribes of animals there are 

 often great diversities in the forms of different individuals 

 of the same species : hence it is necessary that we be 

 w'ell assured that we are examining a normal specimen 

 before coming to any conclusion thereon. This is also 

 very necessary before making drawings of microscopic 

 objects ; and the want of such precaution has led to the 

 pubhcation of many erroneous descriptions. 



Again, in order to unravel the true form and structure 

 of a minute body, it is absolutely necessary that the 

 organs to be examined be perfectly developed ; otherwise 

 it will be difficult, if not impossible, to understand cor- 

 rectly the functions performed by such organs. 



Due regard being had to the above directions, the skill 

 and labour of the preparator will not be wasted. It not 

 unfrequently happens that specimens of certain objects 



N 2 



