Thecium 



thyroid 



of Mosses which bear setae ; 

 The'cium, a layer of tissue below 

 the epithecium, which contains 

 the sporangia in Lichens (Minks), 

 cf. EPITHECIUM, HYPOTHECIUM. 



The'in, the most important alkaloid 

 in the leaves of Thea, the tea- 

 plant. 



The'ke, sometimes used for the theca 

 (ascus) of Lichens. 



theleph'oroid (Thehphorus, e!5os, re- 

 semblance), like the genus Thele- 

 phorus. 



thele'phorus (#17X77, a nipple, <f>opfw, 

 I carry), covered with nipple-like 

 prominences. 



thelotre'moid, having tubercular 

 apothecia like those of Thelotrema. 



thelyg'enous (t)r)\vs, female, yevos, 

 race, offspring), inducing the 

 female element, as ~ Castra'tion, 

 the production of pistils in the 

 male-flowers of a host by Ustilago. 



Theobro'mine, the active principle of 

 the cacao-bean, Theobroma Cacao, 

 Linn. ; theobro'minus, the deep 

 chocolate brown of the seed of the 

 same plant. 



theoretic (deuprjriKbs, speculative), 

 pertaining to theory, as distinct 

 from practice ; ~ Di'agram, a floral 

 diagram of the theoretic com- 

 ponents, not necessarily the same 

 as seen on inspection. 



ther'mic (Bep^, heat), warm ; ~ Con'- 

 stant, the sum of the mean tem- 

 peratures of the days of active vege- 

 tation, up to some definite phase 

 in the plant's life, minus a certain 

 initial temperature determined by 

 several years' observations, and 

 varying for the species (Oettinger) ; 

 Ther'mo-cleistog'amy ( + CLEISTOG- 

 AMY), when flowers do not expand 

 as a consequence of insufficient 

 warmth (Knuth) ; Thennotax'is 

 (rctis, order), changes produced 

 by warmth ; adj. thermotac'tic ; 

 thermoph'ilic(0tXw, I love), applied 

 to those bacteria which thrive in 

 high temperatures ; Thermot'onus 

 (rdvos, strain), the relation between 

 temperature and the manifestation 



of irritability ; thermotrop'ic ( 

 a turning), relating to Thermot'- 

 ropism, curvature dependent upon 

 temperature (Wortmann). 



Thick'ening Lay'er, an apparent layer 

 of cellulose on the inner face of 

 a cell-wall ; ~ Ring, Sanio's term 

 for a ring of meristem in which 

 the first fibro-vascular bundles 

 originate. 



Thigmot'ropism (6iy/j.a, anything 

 touched), curvature induced in 

 climbing plants by the stimulus of 

 a rough surface (Czapek) ; Thigmo- 

 tax'is (rafts, order) is a synonym ; 

 adj. thigmotac'tic. 



Thorn, usually an aborted branch, 

 simple or branched. 



Thread, used by Blair for the FILA- 

 MENT ; Thread-indicator, a form of 

 apparatus for measuring the rate of 

 growth ; thread-shaped, filiform. 



three -an'gled, 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 three 

 principal veins ; ~ parted, tri- 

 partite ; ~ 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, TRITER- 



NATE. 



Throat, the orifice of a gamopetalous 

 corolla or calyx, the fauces. 



Thrum (Grew), Thrumb (Blair), (1) 

 the filament of a stamen, (2) in 

 Composite florets, the anthers ; 

 thrum-eyed, applied to a short- 

 styled dimorphic flower, such as a 

 primrose, the stamens alone being 

 visible in the throat of the corolla. 



Thrush-fun'gus, the disease ascribed 

 to Dfrmaf.ium albicans, Laurens. 



Thun'der-broom = WITCHES' BROOM. 



Thyll, Thyl'la, Thylose, Thy'Uose 

 (Germ. Thylle), cf. TYLOSE. 



thy'roid (Ovpeos, a shield, eI5os, re- 

 semblance), shield-like, peltiform 

 (Heinig). 



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