thermic 



thyroid 



de term ill ed by several years' observa- 

 tions, and varying for the species 

 (Oettinger) ; Thermi'um, a hot spring 

 formation ; Ther'mo-cleistog'amy 

 (+ Cleisto(jamy), when flowers do 

 not expand as a consequence of in- 

 sulhcient warmth (Knuth); ther- 

 monast'ic [uaarhs, pressed), close 

 appression of an organ due to heat ; 

 Thermonas'ty, the condition des- 

 cribed ; thermophilic {<pi\fw, I love), 

 applied to those bacteria whicli 

 thrive in high temperatures; Ther- 

 mo'sis, change due to warmth upon 

 an organism ; Thermotax'is {rd^is, 

 order), movement induced by heat, 

 moving towards its source; Thermo- 

 tox'y {To^iKhv, poison), deatli caused 

 by excess of heat, especially if the 

 plant is short of water (Balls) ; 

 Thermot'onus {t6i/os, strain), the re- 

 lation between temperatuie and tlie 

 manifestation of irritability ; ther- 

 motrop'ic {rpo-rr^, a turning), relating 

 to Thermot'ropism, curvature de- 

 pendent upon temperature ("Wort- 

 mann). 



Therodrymi'um {depos, summer; 

 Spvfxhs, a coppice), leafy-forest 

 formation (Diels); Theromeg'atherm 

 -f Mp.gatherm), having the high 

 summer temperature of 20° C. = 68° 

 F. and above ; Theromes'otherm 

 (-f Mesotherm), with summer heat 

 of 12° - 20° C. = 54° - 68° F. ; 

 therophyH'ous {(pvWov, a leaf), pro- 

 ducing leaves in summer, deciduous 

 leaved plants ; Ther'ophyte {(pvrhv, 

 a plant), a plant which comi)letes its 

 development in one season, its seeds 

 remaining latent during the hot 

 season. 



Thick'ening Lay'er, an a{)parent layer 

 of cellulose on the inner face of a 

 cell-wall ; -- Eing, Sanio's term for 

 a ring of meristem in which the first 

 fibro-vascular bundles originate. 



Thigmomorpho'sis {diyydvu),! touch, -f 

 MoRPHOsis), change in the original 

 structure due to contact, as tlie 

 adhering discs of Aviprlopsis ; Thig- 

 motax'is (-f- Taxis), the result of 

 mechanical stimulus ; adj. thigmo- 



tac'tic ; Thigmot'ropism {rpon^, a 

 turning), curvature induced in climb- 

 ing plants by the stimulus of a rough 

 surface (Czapek). 



Thin'ad {OU, Oiuos, a sand heap, 

 + ad), a dune plant; Thini'um, a 

 dune formation ; tliinoph'ilus((^iA.fa), 

 I love), dune-loving ; Thinophy'ta 

 {(pvrhv, a plant), dune plants 

 (Clements). 



Thorn, usually an aborted branch, 

 simple or branched ; '-' Fo'rest, the 

 Caa-Tinga forests of Brazil. 



Thread, used by Blair for the Fila- 

 MKNT — -blight, the destructive 

 Fungus on tea-plants, Stilbum na- 

 nuni; Thread-ind'icator, a form of 

 a]iparatus for measuring the rate of 

 growth ; thread-shaped, filiform. 



three -an'gied, trigonous ; '^ cleft, 

 trifid ; '-^ cor'nered, -^ edged, with 

 three sides, plain or incurved, and 

 three acute angles, triquetrous ; ~ 

 leav'ed, trifoliate ; — lobed, tri- 

 lobed ; — nerved, with tiiree jirin- 

 cipal veins ; -- parted, tiipartite ; 

 '^ ranked, with three vertical rows 

 on a stem ; ~ ribbed, the midrib 

 and one rib on each side more 

 prominent than the rest ; -^ valved, 

 trivalvate. 



thrice-digita'to-pin'nate = tuiter- 



XATE. 



Throat, the orifice of a gamopetalous 

 corolla or calyx, the fauces. 



Thrum (Crew), Thrumb (Blair), (1) 

 the filament of a st:unen ; (2) in 

 Composite florets, the anthers; 

 thrum-eyed, a])i)1ied to a short- 

 styled dinioii»hic flower, such as a 

 luimrose, the stamens alone being 

 visil>le in the throat of the corolla. 



Thrush-fun'gus, the disease ascribed 

 to Jh-i-'iiatiu/ii albiciui.^, Laurens. 



Thun'der-broom = Witches' iuioom. 



Thyll, Thyl'la. Thy'lose, Thy'llose 

 (Corui. Thylle), cf. Tylose. 



Thy'mol, a crystallized product chieily 

 obtained from the seeds of Onruin 

 coptinLni, but found in many jjlants, 

 as Thyiniia Serpijllum, whence its 

 name. 



thy'roid {Qvp^ls, a shield ; tl5oj. 



384 



