winter-killing 
Xantholeucite 
minates in autumn, and living 
through the winter, fruits and dies; 
of. BIENNIAL ; ~ -kil’ling, destruc- 
tion by exposure to variations of 
weather and temperature; ~ -spore, 
a resting spore. 
Witch’es’ 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’y, a willow twig, a pliable wand. 
Woad, = Isarin, the blue colouring 
matter of Isatis tinctoria, Linn. 
Wood, the lignified portion of plants, 
included within the cambium 
layer, but exclusive of the pith ; the 
xylem elements of the united vas- 
cular bundles; ~ Ball, = SPHERO- 
BLAST; ~ Cells, are lengthened 
and thickened, combined into 
threads, fascicles, or bundles, form- 
ing 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; ~ Parench’yma, tissue 
of thick-walled cells :—Au’‘tumn~, 
the outer portion of each annual 
ring of (eae having smaller 
ducts and wood cells, with walls 
much thickened; Spring ~, the 
inner portion of each annual incre- 
ment, consisting of larger, thinner- 
walled cells and ducts; wood’y, 
approaching the nature of wood, 
ligneous; ~ -Fi'bre, wood-tissue ; 
~ Rings, the annulations seen on 
cross section, which usually denote 
one year’s growth; ~ Tis’sue, xylem; 
_~ Wedg’es, Williamson’s expression 
for the fibro-vascular bundles in 
Calamites (W. R. M‘Nab), 
Wool, long, dense, curled hairs 
(Crozier) ; woolly, lanate, tomen- 
tose, clothed with long and tor- 
tuous or matted hairs. 
291 
worm-shaped, more or less cylindric, 
and contorted. 
Wor’onin’s Hy’pha, a coiled hypha in 
some forms of Ascomycetes, occur- 
ring in the centre of the future 
sporocarp, and probably homo- 
logous with an archicarp. 
Wort, Pe 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, thenon-conduct- 
ing tissue which shuts off fungus- 
diseased portions of bast from 
the sound parts; ~ Gum, a sub- 
stance 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; ~ 
Rot, 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 (De 
Vries). 
Wrap’per, = VOLvVA. 
Wrinkle, a fold or crease ; wrin’Eled, 
rugose, creased. 
Xan’thein (fav@0s, yellow), a yellow- 
colouring of plants, the same 
as ANTHOCHLORIN, ¢f. XANTHINE ; 
xanthel'lus, somewhat yellow; 
xan'thic, tending to yellow; ~ 
Flow’ers, those which display yel- 
low in their tints, opposed to 
eyanic flowers; Xan’thin, (1) a 
pure yellow substance from chloro- 
phyll (Kraus) ; (2) a solid insoluble 
pigment ; also Xan’thine, (1) found 
in seedlings of Cicer arietinum, 
Linn. ; (2) a mixture of colouring 
matters described by Kuhlmann as 
a single body (Green); Xantholeu’- 
cite (+ LxuciTE), a leucite of an 
