250 Anatomy and Physiology of the Family Nepida. (March, 
ANATOMY AND PHYSIOLOGY OF THE FAMILY 
NEPID} 
BY WILLIAM A. LOCY. 
deae value arising from a study of the organs and their func- 
tions in any animal, is not limited to a knowledge of the 
form studied nor to the facts obtained. The general principles of 
comparative anatomy and physiology will be thus developed, 
since they exist in the study of the bodies of all animals, and 
furthermore, the study of a typical form will furnish a key t08 
more special knowledge of a whole group, just as a type lar 
guage affords a key to a group of languages. In studying the s 
anatomy and physiology of the family Nepidæ, then, results are 
obtained which reach far beyond the boundaries of the family 
and which constitute simply special cases to illustrate the pring: 
ples of comparative anatomy and physiology. : 
The functions performed by the organs of animals’ bodies nat | 
urally fall into three groups, nutrition, reproduction and relation, 
which will form special divisions of this subject to be l 
after considering a few generalities. briet 
Methods of work, etc—The more general methods are a) 
considered here, the special methods, when requiring mention, ie ; 
spoken of in connection with the work for which they a 
signed. 
To dissect successfully the Insecta, it is nece 
under water or some other transparent liquid, therefore 4 by 
ing slab and a tray are essential. The former is easily wis bet 
loading cork or soft wood until it will sink under water ; a Me 
ter to paint this black to furnish a good background, sin 5 a 
tissues of insects are usually white. Any vessel of com - 
size will serve as a tray. 
ssary tO wort 
long the melt 
: 
a 
q 
: 
, found 3% 
be founi 
quate for all ordinary work: (1) A pair of fine Se yí 
1 Thesis to obtain the Degree of Master of Science, submitted to the Y 
Michigan. 
