trabeculate 
Transmission 
with cross-bar markings ; trabec’u- 
late, trabecula’tus, cross-barred ; 
Trab’ecule, = TRAPECULA. 
Tra’chea (Lat., the windpipe), a 
spiral duct or vessel; tra’cheal, 
belonging to or resembling tra- 
cheae ; ~ Cells, tracheids ; ~ of the 
vascular bundles, the woody por- 
tion, the cribrose part associated 
with bast ; tra’cheary, =TRACHEAL; 
Tra’cheid (eldos, resemblance), a 
closed cell having secondary thick- 
ening ; vasiform wood-cell of Good- 
ale; ~ Seam, a group of peculiarly 
thickened cells found in the leaves 
of Conifers on both sides of the 
vascular bundle, and formerly re- 
garded as part of the transfusion 
tissue ; Trachench’yma (éyxupo, 
an infusion), tissue composed of 
tracheids or spiral vessels; Tra’- 
cheome, stated by Potonié not to 
be the tracheal, but the hydral 
system of the bundle, he therefore 
names it HyDROME. 
trachycar’pous, -pus (rpaxvs, rough 
to the touch, xapzos, fruit), rough- 
fruited; trachysperm’ous, -mus 
(orépya, a seed), rough-seeded. 
Tractel’lum (tractus, dragged), the 
anterior flagellum of the zoospore 
of Saprolegnieae (Hartog). 
Trag’acanth, a gum which flows from 
Astragalus Tragacantha, Linn. ; 
Tragacan'thin, the same as Bas- 
SORIN. 
trailing, prostrate but not rooting. 
trajec’tile, trajec’tilis (trajectus, a pass- 
ing over), when the connective 
completely separates the anther- 
cells. 
Tra’ma (Lat., weft), a mass of hyphae 
in the lamellae of some Fungi, from 
which the hymenium springs; 
Fayod subdivides it thus: ~ con- 
tex’ta, the hyphae usually parallel, 
or slightly oblique; ~ inver’sa, 
when they are derived from the 
sub-hymenium ; ~ permix’ta, when 
without apparent order. 
transa’pical (trans, across or beyond, 
+ APICAL), used by O, Mueller for 
~ Ax'is, at right angles to the 
§ 
apical axis, passing through the 
centre of the pervalvar (main 
longitudinal) axis of a Diatom; ~ 
Plane, the plane at right angles 
to both valvar and apical planes, 
passing through the pervalvar and 
transapical axis (OQ. Mueller) ; 
Transec’tion (sectio, a cutting), a 
term proposed by C. Macmillan 
for ‘‘ transverse section.” 
Trans fer (transfero, I bring over), of 
water, the passage of water by 
ducts or cells. 
Transforma’tion (transformatio, a 
change of shape), (1) metamor- 
phosis; (2) morphologic changes 
in an organ during its existence ; 
adj. transformed’; as ~ Branch, 
may be a tendril, thorn, or simi- 
larly changed organ; ~ Cell, the 
final shape of the cell, as a fibre, 
tracheid, etc. 
Transfu’sion (transfusio, a pouring 
out), transference; ~ Tis’sue, of 
two kinds of cells; (a) unpitted, 
with abundant protoplasmic con- 
tents; or (b) tracheidal cells, with 
similar contents; ~ Strand, con- 
sisting of parenchymatous or 
slightly thickened cells at the 
junction of the phloém and xylem 
bundle elements, when a ring of 
sclerenchyma is formed. 
Transit’ion (¢ransitio, a passing over) 
Cells, cells which are continuations 
of sieve-tubes, the longitudinal 
division into sieve-tubes and com- 
panion cells stops, and Transit‘ion- 
tissue is formed; transitor’ius 
(Lat., adapted for passing through), 
temporary, soon passing away (8S. 
F. Gray). 
Transla’tor (Lat., a transferrer), em- 
ployed for the RetinacuLum of 
Asclepiads. 
Transloca’tion (trans, across, locatio, 
a placing), the transference of 
reserve material from one part to 
another. 
Transmis’sion (¢ransmissio, a sending 
across), used for the conveyance 
of stimulus as in Drosera and 
Mimosa pudica, Linn., other leaves 
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