PLA- 



243 



PLA- 



level ; forma, shape.] With nearly 

 flat surface ; appl. certain articula- 

 tion surfaces. 



plankton (plangk'tSn) n. [Gk. 

 plangktos, wandering.] The animal 

 and plant life floating through 

 water, including animals with weak 

 locomotory power (biol.}. 



planoblast (plan'oblast) n. [Gk. 

 pianos, wandering ; blastos, bud.] 

 A free-swimming hydroid individual 

 (zool.}. 



Planogamete (plan'ogainef) n. [Gk. 

 pianos, wandering; gamete, a 

 spouse.] A ciliated motile proto- 

 plast or microzoospore of Algae 

 (bot.}. 



planont (plan'ont) n, [Gk. pianos, 

 wandering.] The initial amoebula- 

 stage of Neosporidia (zool.}. 



planta (plan'ta) n. [L. planta, sole of 

 the foot.] The sole of the foot ; 

 the first tarsal joint of Insects. 



plantar (plan' tar) a. [L. planta, sole 

 of the foot.] Pert, the sole of the 

 foot ; appl. arteries, ligaments, 

 muscles, nerves, veins (anat.}. 



plantigrade (plan'tlgrad) a. [L. 

 planta, sole of the foot ; gradus, a 

 step.] Walking with the whole sole 

 of the foot touching the ground. 



plantula (plan'tula) n. [L. plantula, 

 a small sole.] The empodium or 

 pulvillus of Insects (zool.}. 



planula (plan'ula) n. [L. planus, 

 flat.] The ovoid young free- 

 swimming larva of Coelenterates 

 (zool.}. 



planum (plan'um) n. [L. planus, 

 flat.] A plane or area ; appl. cer- 

 tain cranial bone surfaces (anat.}. 



plasma (plaz'ma) n. [Gk. plasma, 

 something formed.] The "liquid 

 tissue " of body fluids through which 

 leucocytes and corpuscles are dis- 

 seminated ; protoplasm generally 

 (biol.}. 



plasm a tic (plazmat'Ik) a. [Gk. 

 plasma, something formed.] Pert. 

 plasma ; protoplasmic (biol.}. 



plasmatoparous (plaz'matop'arus) a. 



Cik. plasma, something formed ; 

 parere, to beget.] Developing 

 a mycelium directly upon germina- 

 tion instead of zoospores, as the 

 grape mildew and other Plasmopara 

 (bot.}. 



plasmocyte (plafmoslt) n. [Gk. 



plasma, something formed ; kytos, 



hollow.] A leucocyte (pkys.}. 

 plasmodial (plazmo'dlal) a. [Gk. 



plasma, a mould ; eidos, form.] 



Pert, a plasmodium. 

 plasmodiocarp (plazmo'dlokarp') n. 



[Gk. plasma, a mould ; eidos, form ; 



karpos, fruit] A modification of a 



ilasmodium in some slime Moulds 



plasmodium (plazmo'dlum) n. [Gk. 

 plasma, a mould ; eidos, form.] A 

 collection of amoeboid masses 

 without nuclear fusion ; the naked 

 protoplasm of Myxomycetes (biol.}. 



plasmogamy , plastogamy. 



plasmolysis (plazmol'isis) n. [Gk. 

 plasma, a mould ; lysis, a loosing.] 

 The withdrawal of water from plant 

 protoplasm, causing contraction of 

 cell walls (bot }. 



plasmosome (plaz'mosom) n. [Gk. 

 plasma, a mould ; soma, body.] 

 The true nucleolus ; cf. karyosome 

 (cyt.}. 



plasmotomy (plazmot'oml) n. [Gk. 

 plasma, a mould ; tome, a cutting.] 

 Division of a plasmodium by cleav- 

 age into two or more multinucleate 

 parts (biol.}. 



plasome (plas'om) n. [Gk. plasma, a 

 mould ; soma, body.] An ultimate 

 vital unit ; a biophore. See hypo- 

 thetical units. 



plastic (plas'tik) a. [Gk. plastos, 

 formed.] Formative ; appl. sub- 

 stances used in forming or building 

 up tissues or organs ; appl. force 

 which gives matter definite form 

 (jhys). 



plastid (plas'tid) n. [Gk. plastos, 

 formed.] A cell-body other than 

 nucleus or centrosome (cyt.}. 



plastidogen organ, the axial organ 

 of Echinoderms (zool.}. 



plastidule (plas'tldul) n. [G\i-plastos, 

 formed.] The ultimate vital unit ; 

 a plasome or biophore. See hypo- 

 thetical units. 



plastin (plas'tln) n. [Gk. plastos, 

 formed.] A substance found in the 

 reticulum of cells (cyt.}. 



plastodynamia (plas'todlnam'ia) n. 

 [Gk. plastos, formed ; dynatnis, 

 power.] Plastic or formative force 

 (Phys.}. 



