GLOSSARY 
419 
Evolu'tion. —The presumable theory that all forms of living things existing today 
have been derived from others previously existing, either by direct descent 
or by common ancestry. 
Exalbu'minous. —Applied to a seed in which the nourishment is stored in the 
embryo during the growth of seed from the ovule stage. 
Excen'tric. —See Eccentric. 
Excres'cence. —A morbid outgrowth. 
Excre'tion. —Getting rid of nitrogenous waste. 
ExcurTent. —Applied to trees, the main stems of which do not disappear in 
branches but grow erect to the summit ending in a terminal bud. The 
opposite of Deliquescent. 
Exfoliate. —To shed layers of bark. To cast off layers of tissue. 
Ex'ine. —The outer wall of a pollen grain. 
Ex'ocarp. —The outer layer of the pericarp. 
Exog'enous. —Applied to the axes of Gymnosperms and Dicotyledons which 
increase materially in diameter. 
Ex'ogens. —Plants with exogenous axes. 
Exospor'ium. —The outer wall of a spore. 
Exert'ed. —Applied to stamens that protrude from the throat of the corolla. 
Exstip'ulate. —Without stipules. 
Ex'tine. —The outer coat of a pollen grain. 
Extrorse'. —Applied to anthers which face outward, away from the gynoecium. 
Face. —The free surface of an organ. 
Fal'cate. —Scythe or sickle-shaped. 
Family.— A sub-division of an order. 
Farina'ceous. —Starchy or mealy. 
Fas'cicle. —A bundle or cluster. 
Fascic'ular. —Belonging to a bundle. 
Fasciculate. —Clustered. 
Fec'ula. —The nutritive part of a cereal. 
Fer'tile. —Producing fruit or reproductive organs. Applied to flowers which 
contain functionally active stamens and carpels. 
Fertiliza'tion. —That method of reproduction characterized by the union of two 
dissimilar gametes. 
Fi'brous. —Fiber-like. Referring to root systems composed of many slender 
rootlets. 
Fibrovas'cular Bun'dle. —A stringy group of fibers, vessels and cells coursing 
through the various organs of the higher plants and serving for support 
and conduction of sap. 
Fil'ament. —The stalk of a stamen; a thread like structure. 
Filamen'tous. —Thread-like. 
FiTiform. —Thread-like. 
Fim'briated. —F ringed. 
