FOBMICIDJE 



133 



FRACTION 



Ant, q.v.: an insect belonging to Hymen- 

 optera. 



Fonnicidse, (for-mi'si-de). [Formica, $..]= 

 Ants: insects living in, communities, belong- 

 ing to Hymenoptera. 



Formionitrile, (for-mi-6-ni'tril). [Formyl and 

 Nitrogen, 2.v.]=:CHN=Hydro-cyanic acid, 

 q.v. Formamide, from which the elements 

 of water have been removed, v. Nitriles. 



Formula, (for'ma-la). [The Latin word.] A 

 general expression, usually in symbols. Ex. 

 H 2 O is the formula for water; CNH that of 

 prussic acid, <bc. 



Formulae, (for'mu-le). [The Latin word.] 

 General expressions, usually in symbols, used 

 in chemistry, mathematics, mechanics, &c. 

 Empirical F. express the actual result of a 

 given experiment. Rational F. express this 

 result in a form denoting some theory. 

 Dental F. express the normal number and 

 arrangement of the teeth; v. Dental formulae, 

 F. of motion: vft; s=$fP: v2=2/s: /=rate 

 of acceleration: Z=time. 



Formulaic equations,(for-mu-la'ik). [Formula, 

 q.v.] Those of which one member is readily 

 seen to be the same as the other, but in a 

 different form: ex. a 2 -b*=(axb)(a-b). 



Formyl, (for'mil). [Formic acid, q.v.]=CT3.O 

 = Radicle, of formic acid, not known in a 

 separate form, formerly also used for Xylyl, 

 q.v. 



Formylia, (for-mi'li-a). [Formyl, 2.v.]=Ethy- 

 lenia, q.v. 



Fornix, ( for'niks ). [ L. fornix, arch. ] A 

 lamella of white fibrous matter in the brain, 

 beneath the corpus callosum. 



Forschammer's regions. Of sea water, v. 

 Regions. 



Forsterite, (fors'ter-It). [Mr. Forster.] A 

 mineral, chiefly silicate of magnesium. 



Fortification, ( for-ti-fi-ka/shun ). [ L. fortis, 

 strong ; facio, I make. ] 1. The science 

 and art of fortifying towns, &c. 2. The 

 buildings intended for defence. 



!Fortin's barometer. A more portable modifi- 

 cation of the cistern-barometer. 



Fortuna, (for-tu'na). [Classical.] No. 19 of 

 the minor planets, q.v. 



Fosse, (fos). [ L. fossa, ditch. ] 1. A ditch 

 or moat. 2. Used in anatomy for any 

 cavity in a bone, <fcc. 



Fossil, (fos'sil). [L.fossilis, dugout.] 1. The 

 remains of any organic substance that has 

 been buried for a long period in the earth. 

 2. The traces, such as casts, of any such sub- 

 stance. F. botany: period of Acrogens=: 

 Silurian, Carboniferous, and Permian rocks; 

 of Gymnosperms=Lower and middle Second- 

 ary rocks ; of Angiosperms=:Cretaceous and 

 Tertiary rocks. F. flax: a loose silky fibrous 

 variety of asbestos. F. flour: remains of in- 

 fusoria; a siliceous mealy earth, used for fire- 

 proof bricks. F. plants: preserved by casts, 

 carbonization, infiltration, and petrifaction. 

 F. paper: a variety of asbestos, named from 

 its appearance. F. screics: casts of the 

 .interior of spiral univalve shells. F. verte- 

 brata: mammalia, as far back as Upper Trias 

 rocks ; birds, as far back as Upper Oolite ; 



reptilia, as far back as Carboniferous rocks ; 



fishes, as far back as Lower Ludlow. Cave 



fossil and semi-fossil remains of Elephas, 



Rhinoceros, Ursus, Hyaena, and Man, q.v. 

 Fossiliferous, (fos-sil-ifer-us). [Fossil, q.v.; 



li.fero, I bear.] F. formations= Aqueous 



formations, q.v. 

 Fougasse, (fo'gas). [The French word.] A 



small mine, used to destroy walls, &c., 



under which it is sunk. 

 Foumart, (fd'mart). [F. fouine, marten; and 



marten, q.v. ]=Mus- 



tela, q.v.; the pole- 

 cat. 

 Fountain.(foun'tan). 



[L. fonx, fountain.] 



A small stream of 



water rising from 



the ground. F. 



% ftskes= Ctenophora: 



whose cilia produce 



small fountain -like 



Foumart, 

 currents. Hero's F.: 



an artificial fountain of water, caused by the 



pressure of air. 

 Fouquieracese, (f5-ke-ra'se-e). [M. Fouquiere.] 



Mexican plants, trees, and shrubs; formerly 



included in Portulaceae. 



Fourth, (forth). In music, the interval be- 

 tween any note and the fourth note above it. 



F. nerve=Trocblear nerve, q.v. 

 Fousel oil, (fu'zel).=Amyl alcohol, q.v. 

 Fovea. (fo've-a). [L. fovea, the pit.] Most 



sensitive point in retina of eye of man and 



apes; a minute circular pi* in the macula 



lutea, where the vision is most distinct. 

 Fovilla, (fo-vil'la). [L. foveo, I nourish.] A 



fluid, containing starch granules and oily 



globules, found in pollen. 

 Fowl, (fowl). [Fugol, the A.-S. name.]= 



Gallus domesticus, q.v. 

 Fowlerite, (fowl'er-It). [Mr. Fowler.] A 



zinciferous variety of Rhodonite. 

 Fox, (foks). [The A.-S. name.]=Vulpes: a 



carnivorous, bur- 

 rowing, dog - like 



quadruped, having 



a bushy tail. Arctic 



f.:=Vulpes lagopa. 

 Fox-bat = Pteropus ' 



personatus: a bat, 



named from its 



fox-like head. 

 Fox-glove=Digitalis, 



from the sJiape of its flowers. 

 Fox-grapes. Plants of N. 



America, belonging to Vi- 



tacese. 

 Fox-shark = Alopecida =( 



charias vulgaris, called also 



sea fox. v. Shark. 



Foxtail grass =Alopecurus, 



q.v. 

 Fracastorius, (fra-kas-to'ri- 



us). A mountain peak in 



the moon. Fox-glove. 



Fraction, (frak'shun). [L. frango, I break.] 



A portion: expressed by two numbers, as 



^> f> V & c -> f which the lower number, 

 the denominator, expresses the number of 



q. 



Fox. 



an herb, named 



