porrect 



preventitious 



porrect', porrec'tus (Lat., stretched 

 out), directed outward and for- 

 ward ; cf. ABBECT. 



por'ulus (Lat.), somewhat porous. 



Por'us = POBE. 



positive, the absolute or effective 

 condition, opposed to negative, and 

 prefixed for emphasis to such terms 

 as Geotropism, Heliotropism, Hy- 

 drotropism, etc. 



poste'rior (Lat., coming after), (1) 

 next or towards the main axis, 

 superior ; the reverse of ANTEBIOB ; 

 (2) in anthers = EXTRORSE ; pos- 

 ti'cal, posti'cous, posti'cus (Lat., 

 that which is behind), on the pos- 

 terior side, next the axis ; extrorse ; 

 Spruce and others use "postical" 

 for the ventral or rooting face of 

 the stem of Hepaticae. 



postventit'ious, -tins (post^HeryVenio, 

 I come), applied to growths which 

 arise subsequent to their normal 

 time ; cf. PKEVENTITIOUS. 



potsn'tial (potentia, force), existing in 

 possibility, not in action ; used in 

 opposition to KINETIC; ~ Gam'eto- 

 pnyte, one which is functionally 

 asexual ; ~ Par'asite, a sapro- 

 phyte which can live equally as 

 a parasite ; ~ Sap'rophyte, a para- 

 site capable of existing as a sapro- 

 phyte. 



Potetom'eter (TTOTTJS, a drink, ^rpov, a 

 measure), apparatus for measuring 

 the amount of water given off by 

 the leaves of plants (Moll) ; Poto- 

 m'eter, a similar instrument for 

 measuring the flow of liquids in 

 tissues (F. Darwin), 

 pott'ioid (eldos, likeness), resembling 



the genus Pottia. 



Pouch = SILICLE ; ~ shaped, hollow 

 and bag-like, as the spur in many 

 Orchids ; diges'tive ~ ; used by Van 

 Tieghem and Douliot for the root- 

 cap of the lateral roots of Legum- 

 inosae and Cucurbitaceae. 

 pow'dery, covered with a fine bloom, 

 as the leaves of Primula farinosa, 

 Linn. 



prae-, or pre- (prae, before), expresses 

 priority in time or place. 



prae'cox (Lat., early ripe), appearing 



or developing early ; precocious. 

 Praeflora'tion (praefloratio, blossom- 

 ing before time) = AESTIVATION. 

 Praefolia'tion (prae, before, folium, a 



leaf) = VEBNATION. 

 prae'morse, praemor'sus (Lat., bitten 

 at the end), as though the end were 

 bitten off. 

 praero'sus (Lat.), apparently gnawed 



off. 

 praeus'tus (Lat., burned at the end), 



looking as if scorched, 

 pras'inous, pras'inus (Lat.), grass- 

 green, leek-green. 



pra'tal (pratum, a meadow), H. C. 

 Watson's term for those plants 

 which grow in meadows or luxu- 

 riant herbage; praten'sis (Lat.), 

 growing in meadows, or pertaining 

 thereto. 



precator'ius (Lat. , relating topetition- 

 ing), used for a rosary, as the seeds 

 of Abnia ; contex'tus, necklace- 

 shaped, moniliform. 

 pre'cius (Lat. ),preco'cious = PEAECOX. 

 predominant, " very conspicuous " 



(Braithwaite). 

 Preflora'tion PRAEFLOBATION ; Pre- 



folia'tion = PBAEFOLIATION. 

 Preforma'tion (pre, before, formatio, 

 a shaping), the theory of the func- 

 tion of germ-plasm, a complex 

 substance whose ultimate factors 

 direct the vital activities of the 

 cell, and resultant form of the 

 plant. 



Prehaustor'ium (pre, before, + HAUR- 

 TOBIUM), papillate epidermal cells 

 of Cuscuta, by which nutriment is 

 obtained before the formation of 

 haustoria (Peirce). 

 premorse' (Crozier) = PEAEMORSUS. 

 Prepo'tency (pre, before, potentia, 

 power), the quality by which cer- 

 tain pollen fertilizes a given pistil, 

 in preference to other pollen. 

 Pres'sure, stress or distributed force 

 causing turgor or compression ; 

 root~, pressure existing in the 

 root-tissues tending to cause the 

 rise of liquid in the stem. 

 preventit'ious (prae, before, venio, I 



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