water-content, the water of the soil or habitat; physiological, the available soil water; physical, the total amount of soil water.

xenodoche (ξένος, strange), an anomalous succession.

xerad (ξηρός, dry), a xerophyte; xerasi´um (ξηρασία, drought), a succession due to drainage or drought; xeriobole (ξηρία, dryness), a plant whose seeds are scattered by dehiscence due to dryness; xerohyli´um (ὕλη, forest), a dry forest formation; xerohylad, a dry forest plant; xerophyll, the leaf of a xerophyte; xerophyte, a dry soil plant; xerophyti´um, a xerophytic formation; xerophilous, dwelling in a dry habitat; xeropoi´um, a heath formation; xeropoad, a heath plant; xerosta´tic (στατικός, standing), used of successions which are completed under xerophytic conditions; xerotro´pic (τροπικός, turning), applied to successions which become xerophytic.

zonation, that condition in which plant groups or formations appear in belts or zones.

zone, a belt of more or less uniform vegetation.

zoochore (ζῶον, animal), a plant distributed by animals.

BIBLIOGRAPHY

Ascherson, P.

Von der Verbreitung der Pflanzen. Leunis Synopsis, 1:724. 1883.

Bachmann, E. T.