autumnal 
axospermous 
autum’nal, autwmna'lis (Lat.), belong- 
ing to autumn ; flowering at that 
season ; ~ Wood, wood formed at 
the close of the growing season and 
notable for its smaller cells. 
Auxan’agrammes (avén, increase, ava, 
up, yeduua, an outline), bacterian 
fields of increase, marked by greater 
development within the diffusion 
area of the nutrient substance 
(Beyerinck) ; Auxanom’eter (uérpov, 
measure), apparatus for measuring 
increase of growth in plants. 
Auxe’sis (avéqyors, growth), (1) dilata- 
tion or increase in the valves of 
Diatoms, etc. ; (2) new formation 
of organs (Czapek). 
Auxiliary (awxriliaris, helpful) Cell, a 
cell borne by a specialised branch 
in certain Algae, which unites with 
the conjugating tube emitted by 
the fertilized trichophore, and then 
giving rise to filaments which bear 
the spores (Osterhout). 
Aux’ospore (atin, increase, ozopd, 
seed), in Diatoms, the spore formed 
by the union of two frustules, 
or the excessive growth of a single 
frustule, whence arises a new bion, 
larger than the parents ; auxoton’ic 
(révos, strain), applied to the move- 
ments incident to increase of grow- 
ing organs, as heliotropism, nuta- 
tion, etc. 
avellan'icus (avellana, a filbert), 
drab, the colour of the fresh shell 
of the Hazel-nut, Corylus Avellana, 
Linn. 
avena’ceous, -ceuws (avena, oats), relat- 
ing to oats; Avenine, a substance 
derived from oats. | 
ave’nius (a, without, vena, vein), vein- 
less, or seemingly so. 
averse’, aver’sus (Lat.), turned back 
or away from. 
Averrunca’tion (averrunco, I remove), 
(1) pruning ; (2) uprooting. 
awl-shaped, narrow and tapering toa 
point ; subulate. 
Awn, a bristle-like appendage, es- 
pecially occurring on the glumes 
of grasses; ~ of Chaetoceras, a 
diatomaceous genus, having pro- 
28 
longations of the frustules, recal- 
ling the awns of grasses; awned, 
having awns; bearded. 
axe-shaped, dolabriform, as the leaves 
of some species of Mesembryanthe- 
mum. 
axial (axis, an axle), relating to the 
axis; ~ Wood, the normal central 
cylinder of xylem ; axif’erous (fero, 
I bear), bearing an axis, but with- 
out leaves or other appendages. 
Ax’il, Axill’a (Lat. arm-pit), the angle 
formed between the axis and any 
organ which arises from it, espe- 
cially of a leaf. 
ax‘ile (axis, an axle), belonging to the 
axis, as axile placentation. 
axill’ant (axilla, arm-pit), subtending 
an angle ; axillary, awilla'ris, grow- 
ing in an axil; axilla’‘tus, having 
axils. 
Ax'is (Lat. an axle), an imaginary 
line, round which the organs are 
developed ; ~ of Inflores’cence, 
that part of the stem or branch 
upon which the flowers are borne ; 
access’ory ~, an axis of secondary 
rank ; a’pical ~ of Diatoms, is 
that line which passes through 
the centre of the pervalvar axis in 
the direction of the raphe and 
at equal distances from homo- 
logous points of the girdle-band 
surfaces; Append’ages of the ~, 
such organs as leaves, flowers, etc. ; 
ascending ~, =the stem ; descend’- 
ing ~,=the root; pervalv’ar~, the 
main longitudinal axis of Diatoms ; 
transa’pical ~, the axis which 
passes at right angles to the apical 
axis of Diatoms, and through the 
centre of the pervalvar axis ; trans- 
vers’al ~, the axis which lies in the 
transversal plane of Diatoms, cut- 
ting the pervalvar axis. 
Axog’amy (diwy, axis, yduos, marriage), 
plants bearing sexual organs on 
the leafy stem; adj. axogam’ic ; 
Axophy’ta (g¢urov, a plant) =Cormo- 
PHYTA ; plants having an axis, that 
is, stem and root; axosperm’ous 
(cvépua, seed), with axile placenta- 
tion of ovules. 
