The development of secondary reflexes probably consists in the establishment of fixed pathways for impulses through the nervous system. Through the branching of the nerve fibers many pathways are open to the impulses. But in repeating the same kind of action the impulses are guided into particular paths, or channels. In time these paths become so well established that the impulses flow along them without conscious direction and it is then simply necessary that some stimulus starts the impulses. By following the established pathways, these reach the right destination and produce the desired result. According to this view, secondary reflex action is but a higher phase of ordinary reflex action—a kind of reflex action, the conditions of which have been established by the mind through repetition. (See functions of the cerebellum, page 317.) *Habits.*—People are observed to act differently when exposed to the same conditions, or when acted upon by the same stimuli. This is explained by saying they have different habits. By _habits_ are meant certain general modes of action that have been acquired by repetition. Certain acts repeated again and again have established conditions in the nervous system which enable definite forms of action to be excited, somewhat after the manner of reflex action. On account of habits, therefore, the actions of the individual are more or less _predisposed_. What he will do under certain conditions may be foretold from his habits. Habits simply represent, a higher order of secondary reflexes—those more closely associated with the mental life and character than are the lower forms. Habits, in common with other forms of secondary reflex action, serve the important purpose of _economizing the nervous energy_. However, if pernicious habits are formed instead of those that are useful, they are detrimental from both a moral and physical standpoint. Youth is recognized as the period in which fundamental habits are formed and character is largely determined. Therefore parents and teachers do wisely when they insist upon the formation of right habits by the young. *Functions of Divisions of the Nervous System.*—The relationship between the different parts of the nervous system is very close and one part does not work independently of other parts. At the same time the general work of the nervous system requires that its different divisions serve different purposes: 1. The peripheral divisions of the nervous system are concerned in the transmission of impulses between the surface of the body and the central system and between the central system and the active tissues. The nerves are the carriers of the impulses. The ganglia contain the cell-bodies which serve as nutritive centers; and, in the case of the sympathetic ganglia, these cell-bodies are the places where the fiber terminations of one neuron connect with, and stimulate, other neurons.