400 BIOLOGY 



exogenous stems (Gr. exo without + genes = a producing) . Stems 

 with a cambium layer separating a bark from a wood ring, 109, 112. 



extensors. The muscles that straighten the appendages at the joints, 211. 



eye, 196; of human being and of frog compared, 367. 



eyespot. A colored spot found in unicellular organisms, sensitive to light, 

 76. 



facial nerve. The nerve supplying the side of the head with sensations, 

 194. 



Fallopian tubes. In mammals the part of the oviduct extending from the 

 ovary to the uterus. 



family. A group of similar genera, 372. 



fat. One of the three chief food substances; a hydrocarbon made up of 

 a fatty acid and glycerine, 9, 133. 



fatty acid. One of the materials into which fat may be decomposed, 10. 



fauna. The total animal life of any region. 



Felis, 372. 



females. Individuals producing eggs, 251. 



female pronucleus. The matured egg nucleus before union with the 

 sperm, 254. 



female spores, 122. 



ferment. Chemical substances that produce fermentation; enzymes, 306. 



fermentation, 79. 



fern, life history of, 269. 



fertilization. The union of the egg nuclei and the sperm nuclei, 122, 

 249, 251, 257, 263. In botany the term is frequently erroneously 

 applied to the transference of pollen to the pistil, 277. 



fibers. The individual elements of muscles and nerves, 170. 



fibrillae. The minute filaments of which a muscle fiber is composed. 



fibrin. A proteid obtained from clotted blood. 



fibrovascular bundles (Lat. fibra = fiber -f- E. vascular). Bundles of long 

 cells of various shapes, extending lengthwise and strengthening the 

 stems of the higher plants, 104. 



fibula, 182. 



filament. The, thread-like stem to a stamen, 119; any thread-like organ. 



fission (Lat. findere = to split). Division into two equal halves, 58, 63. 



flagella (Lat. flagellum = a whip). Rather long, lashing processes of pro- 

 toplasm, one to six to each cell, 73, 218. 



flexors. Muscles that bend the joints, 211. 



flexure. A bending. 



Flora. The total vegetation of any territory. 



flowers, 118. 



foam theory of protoplasm, 31. 



