EVERGREENS 



EXPLOSIVE 



Evolute. 



Evergreens. Plants, such as the holly and 

 laurel, which keep their leaves throughout 

 the winter. 



Everlasting flowers. Those which, from 

 having little moisture to part with, keep 

 the appearance of freshness for a long time. 



Evernic acid, (e-ver'nik). Ci 7 Hi 6 O 7 : an acid 

 obtained from the lichen evernia. 



Evolute, (ev'o-lut). [L. evolvo, I unroll.] A 

 curve, from which an in- 

 volute is formed by the 

 gradual unrolling of a 

 line from its surface. 

 ABC is the evolute, 

 DEFG the involute. 



Evolution, (ev-6-lu'shun). 

 [L. evolvo, I unfold.] 1. 

 The process of finding 

 the square root, cxibic root, &c., of any given 

 number. 2. =Growth (increase of bulk) and 

 development (increase of structure). E. 

 theory: that new species of animals and 

 plants have been developed by a natural 

 process, of which the factors are Heredity, 

 Variation, and Adaptation. 



Ewe, (u). [Eoion, the A. -S. name.] A female 

 sheep, v. Ovis. 



Ex, (eks). [L. ex, from, or out of.] A prefix 

 used to convey the idea of motion from or 

 out of. 



Exalbuminous, (eks-al-bu'min-us). [Ex and 

 Albumin, q.v.} Used in botany to describe 

 seeds that have but little, if any, albumin. 



Exanthalose, (eks-an'thal-5s). [Gk. exantheo, 

 I eftloresce; kals, salt.] An efllorescence of 

 glauber-salt. 



Exanthema, (eks-an-the'ma). [Gk. exanthema, 

 a blossoming.] An efflorescence of the skin. 



Excentric=: Eccentric, q.v. 



Exchange, ( eks-chanj' ). [Echanger, tho 

 French word.] Of heat: of any two bodies at 

 different temperatures near each other, each 

 gives and receives heat until both are it the 

 same temperature. 



Excortication, (eks-kor-ti-ka'shun). [Ex and 

 Cortex.] The removal or falling off of the 

 bark from a tree. 



Excrement, (eks'kre-ment). [Excrementum, 

 the Latin word.] Partly undigested food, 

 partly intestinal secretions; usually of stable 

 chemical composition, and usually acid. 



Excretin, ( eks-kre'tin ). [Excrement, q.v.] 

 Probably CaoHgeO: a crystalline substance 

 obtained from excrement. 



Excretory organs, (eks-kre'to-ri). [L. ex, out; 

 cresco, I grow.] Skin, lungs, and kidneys, q.v. 



Exitelite, (eks'it-e-lit). [Fr. Exitele.]=Valen- 

 tinite, q.v. 



Exocaetus, (eks-o-se'tus). [The Latin name.] 

 = Flying fish: has pectoral fins that can be 

 used as wings to rise 2 or 3 feet from the 

 water. 



Exoccipital, (eks-ok-sip'i-tal). [Ex and Occi- 

 put.] Belonging or relateu to the first cranial 

 segment. 



Exogens, eks'o-jens). [Gk. exo, without; gen- 

 nao, I produce.] A division of flowering plants 

 in which the stem or trunk has a hollow woody 

 axis containing pith; the leaves are usually 



broad and rounded, with net-like veins ; the 

 roots have an exorhizal 

 germination, and a solid 

 woody axis. The plants 

 live for an indefinite 

 time, and never grow 

 from a single terminal 

 bud. They are divided 

 into diclinous exogens 

 and hermaphrodite ex- 

 ogens; and are not found 

 fossil in any primary Exogeii. 



rocks, and very rarely in any bed older than 

 Upper Cretaceous. 



Exogyra, (eks-6-ji'ra). [Gk. exo, without; 

 gyros, curved.]=l. Fossil sponges. 2. An 

 oyster-like fossil. Named from the spiral 

 curve. 



Exorhizae, (eks-o-ri'z5). [Gk. exo, without; 

 rhiza, root.] Plants of which the roots grow 

 from the extremity of the seed, and do not 

 burst through the coat of the seed from 

 within, cf. Endorhizal. 



Exorhizal, ( eks-6-ri'zal ). [Exorhizae, q.v.] 

 Belonging or related to Exorhizse, q.v. 



Exoskeleton, (eks-6-skel'e-ton). [Gk. exo, 

 without; skeletos, skeleton.] The hardened 

 portionsof the in tegument, cf. Eudoskeleton. 

 v. Skeleton. 



Exosmose, (eks'os-mos). [Gk. exo, without; 

 osmos, thrusting.] v. Endosmose. 



Exosperm, (eks'o-sperm). [Gk. exo, without; 

 sperma, seed.] The outer coating of a 

 spore. 



Exoteric, (eks-o-ter'ik). [Gk. cxoterikos, on 

 the outside.] External, popular, opposed to 

 Esoteric, q.v. 



Exothecium, ( eks-o-the'si-um ). [Gk. exo, 

 without; theke, sheath.] The outer covering 

 of a seed-case. 



Exotic, (ekz-ot'ik). [Gk. exotikos, foreign.] 

 Introduced from abroad, cf. Indigenous. 



Expansion, (eks-pan'si-on). [L. expando, I 

 stretch out.] Increase of space occupied by 

 a given quantity of matter. E. of water: 

 takes places in rising above or falling below 

 4 C. E. of gases (including air): about -jf 3- 

 of their volume, at C., for each degree C., 

 and -4^15- for each degree F. E. cam; a cam 

 used to open and shut the valve, admitting 

 the steam in expansive working. Co-efficient 

 of E.: the amount of increase in the volume 

 of a given substance in rising from to 1 C. 



Expansive working, (eks-pan'siv). [Expan- 

 sion, q.v.] In steam engine: in which the 

 supply of steam is cut off before the cylinder 

 is full; the movement of the piston being 

 completed by the expansion of the steam; 

 the object being to economise the steam. 

 E. gear: the machinery requisite for expan- 

 sive working. 



Explosion, ( eks-plo'si-on ). [L. explodo, I 

 drive out.] A sudden and large increase of 

 volume, usually by the conversion of a solid 

 or liquid into a gas. Steam E. '. the fracture 

 of a boiler by the excessive pressure of steam. 



Explosive agents, (eks-plo'siv). Substances 

 by means of which explosions can be pro- 



