iPlAStioity 



Pletotaxy 



starch-grains, proteids, etc. ; Plat- 

 tio'ity, (1) the quality of being 

 plastic ; (2) the condition character- 

 ized by ready response to stimuli 

 (Clements); Plai'tid, Plastid'ium, 

 % protoplasmic granule in active 

 cells, differentiated aa centres of 

 chemical or vital activity, as 

 Chlobo-, Chromo-, and Lxuco- 

 PLASTiD ; '« •col'ourt, those due to 

 plastids in the cells, as distinct from 

 coloured sap (Wheeldale) ; Plas'tid- 

 plasm, { + rLASM), a supposititious 

 substance differing from other forms 

 of protoplasm oy morphological 

 characters (B. M. Davis); PUs'tid- 

 tUe, Elsberg's term for the smallest 

 mass of protoplaiim which can exist 

 as such ; Plas'tin, an essential ele- 

 ment of the entire protoiJasmic cell- 

 contents, including the nucleus and 

 the chromatophores (Zacharias) ; 

 Plastog'amy (7<i/*os, marriage), the 

 fusion of cytoplasts into a Plas- 

 modium, the nuclei remaining dis- 

 tinct (Hartog); adj. plaato^m'io ; 

 Plastog'eny {yivos, race, oflspring), 

 when cytoplastic elements undergo 

 a reorganization by fusion (Hartog) ; 

 Plai'toid (€l8oj, likeness), a needle- 

 shaped body found in the stalk-cells 

 of tne tentacles of Drosera^ becoming 

 rounded under stimulus ; a rhab- 

 doid ; Plaa'toiome {awfta, bodv) = 

 Chondriosome ; Plas'toty^e {rintos, 

 ■ » type), a cast from an origmal type, 



as of a fossO plant. 

 Plat*, a flattened structure ; cf. 



NUCLEAR ^j SIEVE '^ . 



Plate-ringt, the external concentric 

 strands of vascular tissue in Medrd- 

 losa (Jeffrey). 



Plat«»a' (Fr.,), (1) the tubercular disk 

 in a bulb which produces the scales 

 upwards, and the roots downwards, 

 ef. CoBM (Crozier) ; (2) a similar 

 stiucture in certain Compositae, 

 interposed between the ovary and 

 the other floral organs (Lecoq). 



pUtyoar'pio, platycar'pous {xKarhs, 

 broad ; KOfmhs, fruit), broad-fruited ; 

 PUty^nid'ia, pi. (-f Gonidium), 

 guoidia in broadly spreading groups ; 



Platylob'ww {\o$hs, a lobe), used 

 for certain Crucifers with flat coty- 

 ledons ; platyloO)ate, broad-lobea ; 

 platyphyllous {<p<>K\ov, a leaf), 

 broad-leaved ; Plat'yspermi ((rir#>/ta, 

 a seed), applied to certain fossil 

 fruits, flattened in transverse sec- 

 tion ; cf. Radiospkrms (F. W. 

 Oliver) ; adj. platysper'mic. 



Pleoolep'is t> Plecolep'idus {tK^ko), I 

 plait, Xcrls, a scale), the involucre 

 of Compositae when the bracts are 

 united into a cup. 



PleoteneVyma {irXtttrhs, woven ; 

 ^7X«'A»*^ *o infusion), a tissue of 

 woven hyphae ; a pseudo-par- 

 enchyma, further divided into 

 Paraplectenchyma and Proso- 

 PLKCTENCHYMA (Lindau). 



Pl«ioblas'tU8 (irA«to»', more ; fiXcurrhs, 

 a bud), used by Koerber for those 

 Lichen spores which germinate at 

 several points ; Pleioohaslum (x<^*f > 

 separation), each relative main axis 

 of a cyme producing more than 

 two branches ; adj. pleiocluui'ial ; 

 pleiooy'olie (jh/kAos, a circle), peren- 

 nial as - Herbi ; Pleiog'eny (y^vos, 

 race), an increase from the parental 

 unit, as by bmnching or interpola- 

 tion of members ; Pleiom'ery {fihos, 

 a part), having more whorls than 

 the normal niunber ; Pleiomor''pliiiiii, 

 pleioBaor'phy {fiop<i>h, change), the 

 occurrence of more than one inde- 

 pendent form in the life-cycle of 

 a species ; adj. pleiomor'phoai ; Plei- 

 onfifm, Delpino's term for Poly- 

 MOBPHT ; Pleiopet'aly iw4ra\oy, a 

 leaf), doubleness m flowers ( De Vries) ; 

 adj. pleiopet'alouo ; pleiophyrioui, 

 'Iw {(ptiWov, a leaf), with leaves 

 having no apparent buds in their 

 axils ; Pleiophylly, having numerous 

 leaves from the same point, or more 

 than usual the number of leaflets in 

 a compound leaf; Pleiopyre'nium 

 (+ Pyrenium), small apothecia in 

 one verruca, in Lichens ; pUio- 

 gper^moiia (o-r^p/ia, a seed), with an 

 unusually large number of seeds ; 

 Pleiotax'it, Pl«iotax'y (ra^ij, order), 

 increase in the number of whorls in 



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