planiusculus 



Plastin 



divides an object into symmetrical 

 halves ; planius'culus (Lat.), nearly 

 flat. 



Planktol'ogy (7rXa7/cros, wandering, 

 Xdyos, a discourse), the department 

 of pelagic botany, that is, of the 

 floating organisms in the ocean ; 

 Plank'ton, free-swimming or float- 

 ing oceanic life ; fresh'water <~ , 

 that of lakes or rivers ; neritlc ~ , 

 found near the coast; ocean'ic <~, 

 pelagic, far from land. 



Plan'ogamete (TrXcbos, wandering, 

 ya^Tijs, a spouse), a mobile ciliated 

 gamete or zoogamete, as in Chloro- 

 phyceae ; Plan'ospore (cnropai,, a 

 seed), Sauvageau's term for a 

 motile zoospore. 



Plant, Plan'ta, a vegetable production 

 nourished by gases or liquids and 

 not ingesting solid particles of 

 food (except in the plasmodial 

 stage of Myxogastres) ; ~ Cane, 

 the first year's growth of the sugar- 

 cane from seed ; ~ Cas'ein, a sub- 

 stance akin to animal casein ; <~ 

 Forma' tion, an assemblage of plants 

 living together in a community 

 under the same environment, as a 

 moor or wood ; ~ Pathol'ogy, the 

 study of plant-diseases ; Plaii'tae 

 tris'tes, evening flowering plants, 

 as Matthiola bicornis, DC., etc.; 

 plan'tal, pertaining to plants ; 

 Plan'ticle, the embryo in a seed ; 

 Plan'tlet, a little plant ; Plan'tule, 

 Plan'tida = PLUMULE; Plantula'tio 

 = GERMINATION. 



Plasm, Plas'ma (TrXctcr^a, that formed), 

 used for PROTOPLASM ; Plasmamoe'- 

 bae ( + AMOEBA), amoebiform 

 masses of protoplasm, the actino- 

 phrydia of Gobi ; plasmatop'arous 

 (pario, I bring forth), in germina- 

 tion the whole of the protoplasm 

 of a gonidium issues as a rounded 

 mass, which at once becomes coated 

 with a membrane, and puts out a 

 germ-tube ; Plas'masome, or Plas- 

 mat'osome (trw/xa, a body), a proto- 

 plasmic corpuscle, shortened to 

 PLASOME ; plasmat'ic, ready, or 

 serving for growth, plastic ; Plas'- 



mode = PLASMODIUM ; Plasmo'diae, 

 Caruel's term for Myxogastres ; 

 plasmo'dial, plasmo'dic, pertaining 

 to a plasmodium ; Plasmo'diocarp, 

 (/capTroy, fruit), an asymmetrical 

 sporangium of Myxogastres (Rosta- 

 firiski) ; Plasmo'diogens (7^0?, 

 race, offspring), Macmillan's word 

 for the protoplasmic units of a 

 plasmodium ; plasmodioph'oms 

 (0o/>e'w, I carry), producing a true 

 plasmodium ; Plasmo'dium, a mass 

 of naked much-nucleated proto- 

 plasm, showing amoeboid move- 

 ments ; aggregated ^ , the myxa- 

 moebae congregated without fusion, 

 each cell giving rise to a spore or 

 foot-cell ; fused <*- , union of myxa- 

 moebae and subsequent fructifica- 

 tion (Van Tieghem) ; Plasmorysis 

 (X&rts, a loosing), a separation of 

 the living protoplasm from the 

 cell - wall by osmotic action ; 

 plas'molysed, subjected to plasmo- 

 lysis ; adj. plasmolyt'ic ; plasmo- 

 ph'agous (<f>dyw, I eat), absorbing 

 the living organic matter of the 

 host-plant without selection (Boul- 

 ger) ; Plasmosyn'agy (awcfyw, I 

 collect), accumulation of the pro- 

 toplasts of the polioplasm and of 

 the plastids included in it, due to 

 plasmolytic irritation (Tswett) ; 

 Plas'ome, a living element of pro- 

 toplasm, shortened from PLASMA- 

 TOSOME ( Wiesner) ; plas'tic, capable 

 of being moulded or modified; ~ 

 Sub' stances, those employed in 

 building up, as cellulose, starch- 

 grains, proteids, etc. ; Plasticity, 

 the quality of being plastic ; Plas'tid, 

 Plastid'ium, a protoplasmic granule 

 in active cells, differentiated as 

 centres of chemical or vital activity, 

 as CHLORO-, CHROMO-, and LEU- 

 COPLASTID ; Plas'tidplasm, ( + 

 PLASM), a supposititious substance 

 differing from other forms of pro- 

 toplasm by morphological charac- 

 ters (B. M. Davis) ; Plas'tidule, 

 Elsberg's term for the smallest 

 mass of protoplasm which can exist 

 as such ; Plas'tin, an essential ele- 



199 



