meridianus 



Mesophytum 



meridia'nus (Lat. belonging to noon), 

 at mid-day or noon ; towards the 

 south (in northern latitudes) ; 

 meridian, applied by 0. Mueller to 

 the plane in Diatoms which con- 

 tains the pervalvar axis. 



Mer'idisk (nfyos, a part, SiaKos, a disc), 

 term proposed by Clos for any 

 process upon the receptacle apart 

 from the floral organs, whether 

 glandular or not (Crozier); Mer'ism, 

 Bateson's term for the repetition of 

 parts to form a symmetry or 

 pattern. 



merismat'ic (p-epia-^a, a share), divid- 

 ing into parts or similar portions ; 

 Tis'sue, formative tissue, cf. 

 MERISTEM. 



Mer'ispore (fj-epos, apart, airopa, seed), 

 the segment of a sporidesm ; Mer'- 

 istele (ffTr)\-f], a pillar), a portion of 

 the stele of a monostelic stem 

 received by each leaf ; meris'tic 

 Varia'tion, see MERISM. 



Mer'istem (/xepto-ros, divisible), nas- 

 cent tissue, capable of being trans- 

 formed into special forms, as cam- 

 bium, etc. ; Pri'mary ~ , forms the 

 whole tissue of very young organs ; 

 Sec'ondary <~, occurs in organs 

 along with permanent tissue, usually 

 in thin layers ; meristemat'ic, 

 pertaining to the Meristem ; meri- 

 stogenet'ic (yevfT-rjs, a begetter), 

 produced by Meristem, actively 

 dividing cell - tissue ; Mer'ithai, 

 Merithal'lus (da\\os, a young 

 shoot), an internode. 



meroblas'tic (ftepos, a part, /3Xatrr6s, a 

 bud ) Embryog'eny, when only a part 

 of the spore is concerned, cf. HOLO- 

 BLASTIC ; Meroconid'ium, pi. Mero- 

 conid'ia, (+ CONIDIUM), conidia 

 which arise from the simultaneous 

 septation of a hypha in Zygomy- 

 cetes, and mature together, while 

 AOROCONIDIA mature in succession 

 from the apex (A. Fischer) ; meros- 

 as a prefix, and its forms -merous, 

 merus, as suffixes, denote parts or 

 numbers, as dimerous, etc. 



mes'arch (/^eVos, in the middle, dpxTj, 

 beginning), applied by Solms-Lau- 



bach to those bundles in which the 

 protoxylem lies in the interior of 

 the primary strand of the wood, 

 thus partly centripetal and partly 

 centrifugal ; Mesenter'ica (evrepov, 

 an intestine), "the mycelium of 

 certain Fungals " (Lindley) ; Mes'- 

 istem, contracted from Mesomer'is- 

 tem, the thickening ring of Sanio, 

 a ring of tissue producing the bundle 

 system; Mes'oblastfjSXao-ros, a bud), 

 the nucleus ; Mesoblaste'sis, medial 

 growth from Lichen hy phae (Minks) ; 

 Mes'ocarp, Mesocar'pium (Kaptros, 

 fruit), the middle layer of a 

 pericarp ; MesocauleorM'za (KCLV\OS. 

 stem, ptfa, root), Gaudichaud's 

 term for "the line of demarcation 

 between the ascending and de- 

 scending systems in his 'Phyta,'' 

 (Lindley) ; Mes'ochil, Mesochil'ium 

 (xe?Xos, lip), the intermediate part 

 of the lip of those Orchids which 

 have it separated into three dis- 

 tinct parts ; Mes'ochite (XITUV, a 

 tunic), the middle layer surround- 

 ing the egg in Fucaceae, composed 

 of cellulose and attached at the 

 base (Farmer) ; Mesocol'la, ((c6\Xa, 

 glue), a supposed intermediate layer 

 of the cuticle between the upper 

 and lower surfaces ; Mesoder'mis 

 (oep/j.a, skin), the middle layer of 

 tissue in the theca of a Moss ; 

 Mesogonid'ium (+ GONIDIUM), a 

 gonidium which is partially en- 

 veloped in new tissue ; mesogon- 

 im'icus (7o'pijU,os, productive), having 

 the gonidial layer in the centre 

 (Wallroth) ; Mesophlo'em (<p\oibs, 

 bark), the middle, or green bark ; 

 Mes'ophyll, Mesophyl'lum (<pv\\ov, a 

 leaf), (1) the interior parenchyma 

 of a leaf, the whole interior ground 

 tissue of the blade ; (2) the de- 

 marcation between leaf and leaf- 

 stalk ; Mes'ophyte (<pvrdv, a plant), 

 Warming's term for those plants 

 which are intermediate between 

 Hydrophytes and Xerophytes ; 

 avoiding both extremes of moist- 

 ure and drought; Mesophy'tum, (1) 

 a name given by Clarion to the 



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