ex 
Existem 
forms are considered to have been 
evolved from simpler ones. 
ex, privative prefix in place of e, 
when a vowel follows; exo = out- 
ward. 
exalbu’minous, exalbumino’sus (ex, 
priv., + ALBUMEN), destitute of al- 
bumen, used only of seeds when 
the embryo occupies the whole 
cavity within the testa; ex’alate, 
exala'tus (alatus, winged), wingless. 
exalta’tus (Lat., raised high), lofty, 
tall. 
Exanthem’ata (é:, out of, dvOos, a 
flower), blotches on leaves, etc., as 
though eruptive; Exanth’ium ¢ 
bractlets of the last degree, in- 
capable of forming axillary buds, 
and immediately external to the 
flower. 
exan’nulate (ex, priv., annulus, a 
ring), used of Ferns which do not 
possess an elastic ring round their 
sporangia ; exapophysa’tus (+ Apo- 
PHYSIS), destitute of an apophysis, 
or swelling below the capsule of a 
Moss. 
ex/arch (éé, out of, 4px}, origin), used 
of vascular bundles in which the 
whole primary wood is centripetal, 
almost the same as perixylic. 
exar’eolate, exarcola'tus (ex, priv., + 
AREOLATUS), not spaced out or 
marked into small areas; exar’il- 
late (+ ARILLA), without an aril; 
exar istate,exarista’tus(+ ARISTA), 
destitute of awns. 
exas’perate, exaspera’tus (Lat., rough- 
ened), rough with hard projecting 
points. 
ex’cavate (excavatus, hollowed out), 
as though dug out. 
excen’'tric, excentric’'us (ev, out of, 
centrum, the centre), one-sided, 
out of the centre, abaxial. 
Ex’ciple, Ex’cipwle (Crozier), Excip’- 
ulum, Fxcip'ulus (excipula, a basin), 
wart - like excrescences on the 
thallus of certain Lichens, which 
have a narrow opening; the por- 
tion of thallus which forms the 
rim round the base of apothecia. 
Excitabil'ity, Vxcitabil/itas (excitatus, 
roused), the faculty of responding 
to external stimuli. 
excres’cent (excrescens, growing out), 
growing in an unnatural way, as a 
wart or other outgrowth ; Excres’- 
cence, a gnaur or wart on the stem 
of a tree; enation. 
Excre’tion (ex, out of, cretus, sifted), 
(1) the action by which any sub- 
stance is rejected from the organ- 
ism ; (2) the thing itself excreted, 
as gum, resin, honey, etc.; excur’- 
rent, excur’rens (Lat., running), (1) 
running through to the apex and 
beyond asa mucro; (2) where the 
stem remains central, the other 
parts being regularly disposed 
round it; ~ Vena’tion, in Ferns, 
when the veinlet is directed out- 
wards. 
exendosperm’ous (¢£, out, évdov, with- 
in, orépua, seed), used of seeds 
which have reserve material stored 
in the embryo. 
exe’sus {(Lat., eaten away), applied 
to a surface irregularly sculptured 
as though by corrosion. 
exfo'liate (ex, from, folium, a leaf), to 
come away in scales or flakes, as 
the bark of the Plane; Exfolia’- 
tion, peeling off. 
exha’lant (exhalo, I exhale), breathing 
out, as exhalan’tia Va'sat imaginary 
vessels in the epidermis, actually 
the sides of confluent cells; Ex- 
hala’tion, the function discharged 
by stomata in passing off vapour. 
exig’uous, exig’uus (Lat., scanty), 
small and narrow, mean. 
exi'lis (Lat.), thin, meagre ; lank and 
straight. 
exim’ius (Lat., distinguished), ex- 
cellent for size for beauty. 
exindu’siate, exindusia'tus (ex, priv., 
+ INDUSIATE), without an indu- 
sium, the membrane which covers 
the torus in Ferns. 
Ex’ine = EXTINE. 
Ex'intine (ex, out, + Intrnz), the 
middle coat of a pollen-grain, that 
which is next the intine, 
Ex’istem (é£, out, lords, a web), the 
‘« Aussenschicht” of Sanio, consist- 
