MORPnOLOOY. 5 



"through the orderly operations of phj-sical and biological 

 laws, under the guidance of an Infinite Intelligence — a 

 Creator whose modes of working are revealed to us in what 

 Tve call the laws or processes of nature. 

 Zoology is subdivided thus : 



Morphology or gross Anatomy, and minute 



Anatomy (Histology). 

 I Physiology and Psychology. 

 Zoology. ( Reproduction and Embryology. 



Systematic Zoology or Classification. 



Palaeontology. 



Zoogeography. 



Morphology. — In order to properly understand Zoology, 

 •one should first study Morphology — i.e., the general struc- 

 ture of animals. The student should first thoroughly ac- 

 quaint himself with- the anatomy of a vertebrate animal, 

 such as a frog, as compared with that of a toad or salaman- 

 der. The examination and comparison of the organs of 

 animals belonging to distinct groups, is called Comparatire 

 Anatomy. The study of Morphology also includes the rela- 

 tion of the difEerent organs to one another, and of all to the 

 walls of the body, finally, we need also to study the com- 

 position of the tissues of the difEerent organs ; each kind of 

 tissue being formed of different kinds of elements or cells. 

 This department of Comparative Anatomy is called Histol- 

 ogy (Greek, lardi, web or tissue ; \6yoi, discourse). It 

 treats of the cell, and the combination of cells into germ- 

 layers, tissues, and organs. 



The Cell. — The primary elements of the bodies of animals 

 are called cells. They are microscopic portions of proto- 

 plasm either with or without a wall. Protoplasm largely 

 consists of protein, which is a compound of carbon, hydro- 

 gen, oxygen, nitrogen, and sulphur, associated with a large 

 proportion of water. Cells are originally more or less 

 spherical sacs, and the protoplasm forming the cell-mass is 

 the dynamic part of the cell. The protoplasm of animal as 

 well as vegetable cells, the protoplasm of eggs and of the 

 cells forming the difEerent tissues of the animal bodj-, as 



