porrect 



preventitioua 



porrect', porrec'tus ( Lat. , stretched 

 out), directed outward and for- 

 ward ; cf. ARRECT. 



por'ulus (Lat.), somewhat porous. 



For' us = PORE. 



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 ANTERIOR ; 

 (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,&fter,venio, 

 I come), applied to growths which 

 arise subsequent to their normal 

 time ; cf. PREVENTITIOUS. 



potential (potentia, force), existing in 

 possibility, not in action; used in 

 opposition to KINETIC ; ~ Gam'eto- 

 phyte, 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 (TTOT???, a drink, jmtrpov, 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-, orpre- (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) = VERNATION. 



prae'morse, praemor'sm (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. 



precatorlus ( Lat., relating to petition- 

 ing), used for a rosary, as the seeds 

 of Abrus ; ~ contex'tus, necklace - 

 shaped, moniliform. 



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



predominant, "very conspicuous" 

 (Braithwaite) ; in excess (Leighton). 



Prefiora'tlon=PRAEFLORATioN ; Pre- 

 folia'tion PRAEFOLIATION. 



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, + HAUS- 

 TORIUM), papillate epidermal cells 

 of Cuscuta, by which nutriment is 

 obtained before the formation of 

 haustoria (Peirce). 



premorse' (Crozier) = PRAEMORSUS. 



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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