poisonous reptile, etc. These types belong to the Adhibhautikam type, i. e. (brought about by physical causes).
Ka'la-vala-pravritta:—The Periodical type (Kála-vala-pravritta) includes diseases that are brought about by the variation of atmospheric heat or humidity with the change of the seasons, and admits of being grouped under two different sub-heads, according as the seasons, which usher these changes in, exhibit natural or contrary features.
Daiva-vala-pravritta:—The Providential (Daiva-vala-pravritta) type includes diseases that are the embodiments of curses, divine wrath or displeasure, or are brought about through the mystic potencies of charms and spells, as described in the Atharva-Veda. This type may be divided into two minor divisions according as the disease is due to such acts of God as when a man is struck by lightning, etc., or to the malignant influences of demons and monsters, and these may be further grouped under two main sub-heads, according as the disease assumes a contagious character (epidemic), or is purely accidental, and restricts itself to isolated cases (sporadic).
Svabha'va-vala-pravritta:—The Natural or the Spontaneous (Svabháva-vala-pravritta) type includes such natural organic phenomena as,
