GLOSSARY 315 
Os. A prefix signifying inversion. Note Obovate, Oblique, 
Oblong, Obtuse, Opposite, etc. 
OBLIQUE (obliquus = slanting). Unequal-sided. Deviating 
irregularly from a direct line. 
Ostone (longus = long). A four-sided form longer than 
broad. 
OBTUSE (ob = against; tundere = to beat). Blunt or 
rounded at the point. . 
OpposITE (ob = against; positum = placed). Applied to 
leaves and branches placed in pairs on opposite side of 
stems, and in contradiction to the description ALTERNATE 
(q. vide). 
OvaTE (ovum = an egg). Egg-shaped, broader at base. 
Obovate represents shape of an egg turned upside down, 
and therefore broadest at the apex. 
Ovor. Ditto. Egg-shaped. 
OvuLe. Vide PisTi1LLaTE. An incipient seed. 
PECTINATE (pecten = a comb). Applied to trees—e.g. Silver 
Firs—whose leaves are arranged like the teeth of a comb. 
PEDICcEL and PEDUNCLE (pediculus, petiolus, and pedunculus, 
all refer to a little foot). Terms used to describe the 
various kinds of foot-stalks. 
PEDIcEL. The stalk of a separate flower in a compound 
cluster. 
PEDUNCLE. The main stalk which joins the cluster to the 
twig or branch, or the stalk of a solitary flower or fruit 
(e.g. an acorn). 
PELTATE (pelta = shield) shield-shape. Applied to leaves, 
cones, etc., attached to their stalks by the centre, not the 
margins, ¢.g. a mushroom, a Chamacyparis cone, etc. 
PERSISTENT (persistere = to continue). Applied to the 
length of time leaves and cones of conifers remain on the 
tree. 
PETIOLE. The stalk of a leaf. Vide PEpiceL. 
PuyYLioips (Gk. phyllon = leaf). A growth half petiole, half 
leaf, used in connection with growths on Japanese 
Umbrella Tree. Synonyms: CLapoDES, HERBACEOUS 
BRANCHLETS (q. vide). 
PINN# (pinna = feather). 
PINNATE. Shaped like a feather. Applied to leaves arranged 
