PART IL 
DESCRIPTION OF PLATES. 
+ 
Tue plates in this little work have been se- 
lected and arranged not only for the purpose 
of showing what photo-micrographs are, how 
they are made, and what microscopic objects 
are best suited for photography, but also with 
a view to conveying, by the pictorial method, 
some elementary biological information. 
The writer hopes that the volume will be 
useful not only to those who propose to make 
photo-micrographs, but to those who are seeking 
information, and to whom the wonders of the 
microscopic world are comparatively known. 
The effort will, therefore, be made to give a 
popular character to this part of the work, and 
it may be that the title, ELEMENTARY LEssONs IN 
BroLoey, would not be considered out of place 
at the head of this section. The less pretentious 
title is, however, selected, with the understanding 
that if the writer’s opportunities permit, and a 
reasonable demand on the part of the public 
