GLOSSARY 379 



Fertilization (fer' ti li za' shun). The union of an egg with a spermatozoon, a process 



requisite, in the higher animals, to the development of the egg. 

 Fibril (fi' hril). One of the longitudinal contractile threads of a voluntary muscle celL 

 Fibula {fib' u la). The outer one of two bones in the lower leg of vertebrates except 

 the fishes. 



Filar (fi' lar). Composed of threads; used in describing some forms of protoplasm. 



Fission {jish' un). The division of an organism into two approximately equal parts; 

 or, simply, division. 



Fix (fiks). To convert into compounds; said of the action of certain bacteria on the 

 nitrogen of the air. 



Flagellate iflaj' el late). Possessing flagella, or pertaining to or performed by flagella. 

 As a noun, a flagellate protozoon. 



Flagellum [flajeV lum) (pi., flagella). A long whip-like motile projection from a cell. 

 Flame cell (flame' seV). A cell having a hollow interior in which a bunch of vibratile 

 cilia are located, forming part of a protonephridium. 



Flemming, W. {flem' ing). A German biologist. 



Flora iflo' ra) . The plants of a given area or of a given period of time, taken collectively. 



Fluctuating variation {fluk' tu a ting va' ri a' shun). A modification of an organism 



which is not inherited, and which is presumably due to the environment in a 



broad sense. 

 Fluke (fluke) . Any one of several species of trematode worms. 

 Foot (foot). The basal muscular part of a clam or snail, variously modified in many 



other moUusks. Also the terminal part of a leg, the base of Hydra, etc. 

 Foraminal aperture (fo ram' i nal ap' er ture). In a sponge gemmule, the opening 



in the shell through which the young sponge escapes when it begins to develop. 



Formaldehyde (for maV de hide). A gas whose formula is HCHO. 



Fossil (Jos' sil). The remains, or other indication, of a prehistoric animal or plant. 



Fungia (fun'ji a). A genus of corals, of the phylum Ccelenterata. 



Furcula (fur' ku la). The wishbone of a bird, consisting of the fused clavicles of the 

 two sides. 



Galen (ga' len). Famous Greek physician and anatomist, born about 130 A.D. 



His writings were long the highest authority in medical science. 

 Gall bladder (gawV blad' der). A pouch in which the bile secreted by the liver is 



stored. 

 Galvanotaxis (gal' van o tak' sis). An orientation of an organism with reference 



to the stimulus of an electric current. 

 Galvanotropism (gaV van of ro piz'm,). The response of an organism to an electric 



current. 

 Gamboge (gam' boje). A resinous substance. 

 Gamete (gam' eet). A germ cell, or other cell which fuses with a second cell in 



reproduction. 

 Ganglion (gang' gli on) (pi., ganglia). A mass of nerve cell bodies, usually forming 



a thickening in the course of a nerve. 

 Gasterosteus (gas' ter os' te us). A genus of fishes, the sticklebacks. 

 Gastric (gas' trik). Pertaining to the stomach. 



Gastrocnemius (gas' trok ne' mi us). A large muscle in the calf of the leg in verte- 

 brate animals. 



