Winter 



Xanthine 



and temperature ; -^ Eot, a disease of 

 stored potato-tubers, due to Ncctria 

 Solani ; ~ spore, a resting spore. 



Witches' Brooms, a disease shown by 

 tufts of shoots, due to attack by 

 Fungi or mites; in German " Hex- 

 enbesen "; Steppe-wit'ches, or Wind- 

 ^ , ball-like felted masses of plants 

 in steppe regions, which have become 

 detached from their roots and are 

 blown about by the wind. 



with'ering, marcescent. 



With'er-tip, of Citrus, due to Colleio- 

 trichum gloeosporoidcs. 



With'7, a willow twig, a pliable wand. 



Woad, = IsATi.v, the blue colouring 

 matter of Isatis finctoria, Linn. 



Wood, the lignified portion of plants, 

 included within the cambium layer, 

 but exclusive of the pith ; the xylem 

 elements of the united vascular 

 bundles ; -- Ball,= Si'HEROblast ; ~ 

 Cells, are lengthened and thickened, 

 combined into threads, fascicles, or 

 bundles, forming prosenchyma; ~ 

 El'ements, the fibres which make 

 up the xylem ; ^ Fi'bre, the fibro- 

 vascular tissue ; ~ Gum, contained 

 in the wood of Dicotyledons, said to 

 consist chiefly of xylan ; ~ Paren- 

 ch'yma, tissue of thick-walled cells; 

 ~ Eay = Medui.laky Ray ; ~ Kot, 

 due to Stereum hirsutum, Fr. ; 

 Au'tumn '^, the outer }K)i-tiou of 

 each annual ring of growth, having 

 smaller ducts and wood cells, witli 

 walls much thickened ; crypto- 

 gam'ic '^ , tiic centripetal portion of 

 the xylem in the stem of Cycadoxy- 

 leae ; Spring ~ , tlie inner portion 

 of each annual increment, consisting 

 of larger, thinner-walled cells and 

 ducts. 



Woodland, wocnly plants dominating 

 the vegetation. 



wood'y, approaching the nature of 

 wood, ligneous ; -^ Fi'bre, wood- 

 tissue ; -^ Bings, the annulations 

 seen on cross se6tion, which usually 

 denote one year's growth ; ~ Tis'sne, 

 xylem ; ~ Wedg'es, Williamson 6 

 expression for the fibro- vascular 

 bundles in CnJamitcs {\S . R. Al 'Nab). 



Wool, long, dense, curled hairs 

 (Crozier) ; wool'ly, lanate, tomen- 

 tose, clothed with long and tortuous 

 or matted hairs. 



worm-shaped, more or less cylindric, 

 and contorted. 



Woro'nin's Hy'pha, a coiled hypha in 

 some forms of Ascomycetes, occur- 

 ring in the centre of the future 

 sporocarp, and probably homologous 

 with an archicarp. 



Wort (pr. wurt), (1) a plant, especially 

 a cabbage ; (2) the sweet infusion of 

 malt, or unfermented beer 



Wound, any injury caused by abrasion 

 or incision in the cortical layers of 

 a tree ; -^ Cam'bium, a layer of 

 phellogen resulting from the tan- 

 gential division of epidermal cells, 

 or from cortical cells beneath the 

 epidermis ; ~ Cork, the non-conduct- 

 ing tissue which shuts off fungus- 

 diseased portions of bast from the 

 sound parts ; ~ Oum, a substance 

 abundantly secreted in the vessels 

 by the surrounding starch-cells, 

 closing the wound-cavities (Temme) ; 

 ~ Par'asite, a Fungus which attacks 

 the surface of a wound, and so effects 

 an entrance into the tissues of the 

 host ; '^ Eot, various forms of decay 

 not accounted for by parasitic Fungi ; 

 '-' Wood, abnormal growth, dis- 

 tinguished by its short cells and 

 absence or scarcity of vessels (I)e 

 Vries). 

 Wrap'per = Volva. 

 Wrin'kle, a fold or crease ; wrin'kled, 

 rugose, creased. 



A' - Genera' tion (Lotsy) =nAMEr(v 



I'llYTE. 



Xan'thein {^avdhs, yellow), a yellow- 

 colouring of plants, the same as 

 Antiiochlorin, cf. Xanthink; 

 xanthel'lus, somewhat yellow ; 

 xan'thic, tending to yellow ; ~ 

 Flow'ers, those which display yel- 

 low in their tints, o|)])osed to cyanic 

 flowers ; Xan'thin, (1 ) a pure yellow 

 sul 'Stance from chlorophyll (Kraus) ; 

 (2) a solid insoluble ]»igment ; also 

 Xan'thine, (1) found in .seedlings of 



409 



