Polypetalous. — H aving many petals. 
Pomum. — T he Pomum is a fleshy or pulpy pericarp or fruit, 
without valves, but enclosing a capsule, which is a 
thin and membranaceous substance, consisting for the 
most part of five distinct cells. It is exemplified in 
the familiar case of the apple, from the Latin appel- 
lation for which it has taken its name. 
Pores. — Pores are openings or presumed openings in the 
membrane composing the cellular or vascular tissue 
of the interior of the plant. Mirbel advocates the 
doctrine of their existence, and Dutrochet denies it. 
Prickles. — Prickles are stiff and sharp-pointed processes issu- 
ing from the stem or branch, and originating in the 
bark, with which they may be entirely stripped off. 
In this respect they differ from thorns, which have 
their origin in the wood. They are well exemplified 
in the Rose or Bramble. 
Primine. — The outermost of the coats that envelopes the ovu- 
lum in its early state has been by Mirbel denominated 
the Primine; and botanists seem to have adopted the 
term. 
Propago. — According to Gcertner, the Propago is a simple 
gem reproductive of certain genera of Cryptogam ous 
plants, particularly the Lichens. It is a small and 
pulpy granule of no regular shape, naked, or covered 
with an envelope, and equivalent to the spores of 
modern botanists. 
Proliferous Flower. — If a flower protrudes other flowers 
from within in its own disk, it is said to be proli- 
ferous, as in Cliilding Daisy. 
Pubescence. — Pubescence is a general term including all 
sorts of cuticular processes or prolongations with 
which the surface of the plant may be covered, finer or 
less formidable than the armature, such as hairs, 
hooks, scales, down. 
Pulp. — The Pulp is a term that may be regarded as synony- 
mous with that of the Cellular Tissue. 
Pulvinus. — M. Link has given the name of Pulvinus to the 
small protuberence that is found on the stem or branch, 
immediately under the cicatrice which the leaf leaves 
behind by its fall. 
Putamen. — The Putamen of Gcertner, which is equivalent to 
the endocarpium of Richard, is the shell of the nut, or 
the stone of the Drupe, as exemplified in the Filbert 
and Peach. It does not open spontaneously. 
Py^rena. — If a Putamen is composed of several cells, each cell 
takes the name of pyrena, as in cornus. 
Pyxidium — The Pyxidium is a one-celled capsule, which has 
become so by the obliteration of the dissepiments of 
several carpella : and in which the suture of dehis- 
cence is transverse to that of the valves, as in Ana- 
gallis arvensis. 
Quartine. — If the chorion or nucleus of the ovulum developes 
a secondary integument, it is, according to Mirbel, to 
be called the quartine. 
Radicle. — The Radicle is that portion of the embryo which in 
germination, descends into the soil, and becomes the 
root, or caudex descendens, of Linnaeus. 
Raceme. — The Raceme is merely a different term for that 
mode of inflorescence which is called the cluster. 
Rachis. — The flexuose axis of the inflorescence of the grasses 
is denominated the Rachis, and the term is also ap- 
plied to denote the midrib of the Frond of Ferns. 
Ramenta. — The small and scattered scales that are frequently I 
found on the stems of vegetables originating in the 
bark, and giving it a rough or chopped appearance, 
were by Linnaeus denominated Ramenta. They are 
peculiarly conspicuous on the stem or branches of 
Tamarix gallica. 
Ramose. — The Ramose or branched root, is a very common 
species, being that of most trees and shrubs. 
Raphe. — The Raphe is the internal umbilical cord, which 
passes from thehilum or base of the seed to the chalaza. 
Raphides — The raphides are small and needle-shaped sub- 
stances, interspersed throughout the cellular tissue, 
or proper juices of many plants. They are said to be 
crystals of oxalate of lime. \Raspail.~\ 
Rays. — The divergent layers seen on the tranverse section of 
the stem of woody plants are often designated by the 
appellation of the medullary rays. The outer petals 
of a compound radiate flower are also designated by 
this name. 
Receptacle. — With botanists, the receptacle is the base on 
which the several parts of the fructification rests ; that 
is, the extremity of the peduncle, which undergoes 
many modifications in accommodating itself to the 
form of the flowers and fruits of the different families 
of plants. 
Regma. — I f a pericarp consist of three or more cells which 
burst from the axis with elasticity into two valves, it is 
called a regma, and the several cells are called cocci. 
It is exemplified in Euphorbia. \_Lindley.~\ 
Reniform. — Kidney-shaped. When the apex of a leaf is broad 
and rounded, and the base deeply hollowed out in the 
shape of a kidney. 
Replum. — When the two sutures of a silique separate from 
the valves, they form a kind of frame called replum, 
as in Cheiranthus. 
Resupinate. — When the surface of a leaf which is commonly 
undermost, is found uppermost, 
Retuse. — When the apex is obtuse, with a broad shallow notch 
in the middle. 
Ringent.— G aping. 
Ringent Corolla. — When two lips of a labiate flower are 
separated from each other by a wide and regular ori- 
fice, the corolla is said to be ringent. 
Root. — The root is that part of the plant by which it attaches 
itself to the soil in which it grows, or to the substance 
on which it feeds, and is the principal organ of nutrition. 
Rootstock. — The rootstock,, rhizoma, “ is a prostrate thick- 
ened rooting stem, which yearly produces young bran- 
ches or plants. It is chiefly found in the Iridece and 
epiphytous Orchideee ” [ Lindley ,] and in some Ferns. 
Rootlets, or fibres are the essential organs by which ab- 
sorption of nutriment is effected . 
Rugose. — Applied to leaves with inequalities rising above the 
veins. 
RuNciNATE. — When the expansion of a leaf is deeply cut into 
many transverse acute-angled segments, the points of 
which tend towards the base of the leaf. 
Runners. — Runners are young shoots, issuing from the col- 
lar, or summit of the root, and creeping along the 
surface of the soil, but producing a new root at the 
extremity, and forming a new individual, by the decay 
of the connecting link. This takes place in a great 
variety of herbs, but particularly in the Strawberry, 
which is a good example. 
Sacculus Coliquamenti. — By this appellation, Malpighi de- 
signated the fine, thin, and pellucid membrane, with 
which the amnios is found to be sometimes invested. 
Samara. — This term was employed by Gaertner to denote a 
species of capsule, which is described as being inde- 
hiscent, winged, one or two celled, but without valves, 
as in the ash, elm, and maple. 
Sap. — If a branch of the vine, Vitis vinifera, is cut asunder early 
in the spring, before the leaves have begun to expand, 
a clear and colourless fluid will issue from the wound, 
and will continue to flow copiously for a considerable 
length of time. It is merely however, the ascending 
sap, and may be procured from almost any other plant 
by the same or similar means, and at the same season, 
but particularly from the maple, birch, and walnut- 
tree, by means of boring a hole in the trunk. It issm s 
chiefly from the tubes of the alburnum, though in 
some plants, it does not flow freely till the bore is car- 
ried to the centre. A small branch of a vine has been 
