Part 40

=Oxygen=, n. One of the gases that compose the air and which is essential to life. It is also found in composition in the tissues of plants and animals.

=Pelargonium=, n. From a Greek word meaning “a stork”; a member of the Geranium Family, so called because of the beaked seed-pods.

=Petal=, n. From a Greek word meaning “a leaf”; one of the leaves of a corolla.

=Phosphorus=, n. From a Greek word meaning “Lucifer, the morning star”; a solid substance which is luminous in the dark. It is found in composition in the bodies of animals and plants.

=Pioneer=, n. L. pes, a foot; in military terms, one of a company of foot soldiers who march before an army with implements to clear the way. Hence, whoever or whatever leads or prepares the way for others coming after.

=Pistil=, n. L. pistillum, a pestle; the seed-bearing organ of a flower, composed generally of three parts, ovary, style, and stigma, and called pistil because of its shape, which often resembles a pestle.

=Plant cells=, n. The cells of which plants are built up.

=Pollen=, n. L. pollen, fine flour; the dust or grains of fertilizing material found in the anthers of flowers.

=Pollen cells=, n. The grains of pollen; each grain is a separate cell.

=Polypetalous=, a. From two Greek words meaning “many” and “leaf.” Said of a flower having two or more separate petals.

=Potash=, n. A combination of potassium, carbon, and oxygen. Potash in various forms is found in all plants.

=Potassium=, n. A substance found in combination with other things in the earth’s crust, and in the form of potash, an important factor in the substance of plants and animals.

=Potato=, n. One of the edible tubers of the potato plant. The potato is a swollen underground stem, the eyes being the nodes. The potato contains a large amount of starch and is a valuable food. The potato plant is a native of the Andes. It was taken to England from Virginia in 1856.

=Prickles=, n. A.-S. prica, a sharp point; small, sharp-pointed growths from the bark of plants.

=Primitive=, a. L. primus, first; pertaining to the beginning or origin of a thing. In botany, beginning to take form, applied to an organ or structure that is just beginning to assume form.

=Primus=, n. L. primus, first; a name given in this book to a suppositional plant.

=Probing=, n. L. probare, to test, examine; examining by means of a long, pointed instrument or probe. The bee or butterfly probes for nectar with its long tongue.

=Protean=, a. Pertaining to Proteus; readily assuming different shapes.

=Proteus=, n. In classical mythology, a sea god who had the power of assuming different shapes. He could become a serpent or a cloud or a bull or anything he chose to become.

=Protoplasm=, n. From two words meaning “first” and “form.” A substance resembling the white of an egg in appearance, composed of carbon, hydrogen, oxygen, nitrogen, sulphur, and phosphorus. It is the foundation of all living forms.

=Protoplasmic=, a. Consisting of protoplasm.

=Quartus=, n. L. quartus, fourth; the name given in this book to a suppositional plant.

=Quintus=, n. L. quintus, fifth; the name given in this book to a suppositional plant.

=Rain=, n. A.-S. regn, rain; the water falling in drops through the atmosphere. Water rises as vapor from the moist earth and the sea; it is then condensed by coming in contact with the cold upper air, and falls to the earth as rain.

=Reproduced=, pp. L. re, again, producere, to produce, to bring forth; produced again, having formed new plants or animals from those already existing.

=Retrogressed=, pp. Went backward.

=Retrogression=, n. L. retro, backward, gradi, to go; the act of going backward.

=Rhea=, n. In classical mythology, the wife of Saturn and mother of Jupiter.