Exhomotropy 



Ezosmose 



condition described ; Exhy'menine 

 (ujUTjy, a membrane) = Extine. 



exig'uous, exig'uus (Lat., scanty), 

 small and narrow, mean. 



ex'ilis (Lat), thin, meagre ; lank and 

 straight. 



exim'ius (Lat., distinguished), excel- 

 lent for size, for beauty. 



exindu'siate, exindvsia'tus {ex, priv., 

 4- iNDUsiATE), without an indusium, 

 the membrane which covers the torus 

 in Ferns. 



Ex'ine = Extine. 



Exlntine (ex-, out ; + Intine, the 

 middle coat of a pollen grain, that 

 which is next the intine. 



Ex'iscem (e'l, out; iarhs, a web), the 

 " Aussenschicht " of Sanio, consist- 

 ing of Mesistem, "thickening ring" 

 and Perisiem, young cortex ; it is 

 the tissue of i>rotomeristem which is 

 not young pith. 



Ex'it, the inner a^-erture of the 

 slit of a stoma; in Germ, "Aus- 

 gang." 



exo, prefix = outward : Ex'ocarp, Exo- 

 car'pium (€|co, outside; Kapnhs, fruit), 

 the outer layer of a pericarp ; Exo- 

 caryog'amy {Kapvov, a nut; 70^05, 

 marriage) = Exogamy ; exocatad'ro- 

 mous (+ CATADKOMOUs). when Ferns 

 in their nervation have their stronger 

 pinnules anadromous, and their 

 weaker catadromous (Prantl) ; Ex'o- 

 chite {x^Twv, a tunic), the outerm 'St 

 membrane of the egg in Fucaceae 

 (Farmer) ; Exocho'mophyte (x^."". 

 a mound ; (purhv, a plant), surface- 

 rooting and mat-forming plants. 

 Exocor'tex {cortex, bark), (1) the 

 outermost portion of the cortex ; (2) 

 in Rhizomorphae specially pervaded 

 by hyphae : (3) as[)ecial layer in the 

 roots of saprophytic Orchids ; Exo'- 

 dermis (5€V,ua, skin), the outermost 

 cortical layer of the adult root, 

 answering to the hypodernia of the 

 stem ; exogam'ic {yd/jios, marriage), 

 .when Howers are crossed from diller- 

 ent plants (K. Pearson) ; Exog'amy 

 {yd/jLos, marriage), (1) the tendency 

 of closely allied gametes to avoid 

 pairing ; (2) the union of two gametes 



of distinct broods (Haitog) ; exog'- 

 enous, exog'enus {ysvvdo), I bring 

 forth), (1) growing as the wood of 

 Dicotyledons ; (2) arising from super- 

 ficial tissue ; Ex'ogens, Exog'ena-i, 

 plants which increase in growth by 

 the addition of wood on the outside 

 beneath the constantly widening 

 bark ; exog'ynous, cxoy'ynus (7uu^, 

 woman), where the style is exserted 

 beyond tlie flower ; exohadromat'ic 

 (+ Hadkome), exterior to the had- 

 rome ; cf. perihadromatic ; Exo- 

 isog'amy ( + Isogamy), when a 

 gamete will pair only with a himilar 

 gamete of another brood (Hartog) ; 

 Exoraer'istem (+Mrristem), Rus- 

 sow's term for the meristem which 

 produces all the tissues of a Moss 

 outside the central-strand, namely, 

 cortex and epidermis (Vaizoy) ; exo- 

 nas'tic {vaarhs, pressed close), in 

 anatropous or campylotropous ovules 

 when the curvature is, horizontal 

 towards the median nerve of the side 

 of the upper face of the carpel (Van 

 Tieghem) ; cf. endonastic ; Exo- 

 neuro'sis, {v^vpov, a nerve), the 

 separation of veins in appendicular 

 organs, and their reappearance as 

 teeth, spines, or brisiles, as in the 

 Harberry (Clos) ; Exoperid'ium ( + 

 Periditm), the outer layer of the 

 peridium of su. h Fungi as Ly coper- 

 don, which peels or flakes off on 

 maturity ; exophyl'lous, -iis {<pv\\ou, 

 a leaf), not having a foliaceous 

 sheath, with naked cotyledons ; 

 Exopleu'ra {TrXfupa, the side) = 

 Testa (Heinig) ;. Exoprothal'leae, 

 Van Tifghem's term for vascular 

 Cryptogams ; exop'tile, exop'tilis 



{tttIXou, a wing) = EXOPHYLLOUS, 



said of an embryo whose plumule is 

 naked upon or between cotyledons 

 and not rolled up in one (Lindley) ; 

 Exorhi'zae (^jC«, a root), = Kxo- 

 gens ; exorhi'zal, exorliiza'H<, the 

 radicle not sheathed, so the primary 

 root in germination has no covering 

 to pierce; Exosclero'tes (trvArj^i/s, 

 hard), sclerot'.a which arc external to 

 the surface of Agarics ; Exos'mose, 



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