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INTRODUCTION.

although they very frequently also retain the green colour of the leaves. When small they are often called scales.

61. Floral leaves or leafy bracts are generally the lower bracts on the upper leaves at the base of the flowering branches, intermediate in size, shape, or arrangement, between the stem-leaves and the upper bracts.

62. Bracteoles are the one or two last bracts under each flower, when they differ materially in size, shape, or arrangement from the other bracts.

63. Stipules are leaf-like or scale-hke appendages at the base of the leaf-stalk, or on the node of the stem. When present there are generally two, one on each side of the leaf, and they sometimes appear to protect the young leaf before it is developed. They are however exceedingly variable in size and appearance, sometimes exactly like the true leaves except that they have no buds in their axils, or looking like the leaflets of a compound leaf, sometimes apparently the only leaves of the plant ; generally small and narrow, sometimes reduced to minute scales, spots, or scars, sometimes united into one opposite the leaf, or more or less united with, or adnate to the petiole, or quite detached from the leaf, and forming a ring or sheath round the stem in the axil of the leaf. In a great number of plants they are entirely wanting.

64. Stipellce, or secondary stipules, are similar organs, sometimes found on com- pound leaves at the points where the leaflets are inserted.

65. When scales, bracts, or stipules, or almost any part of the plant besides leaves and flowers are stalked, they are said to be stipitate^ from stipes^ a stalJc,


§ 7. Inflorescence and its Bracts. QQ. The Inflorescence of a plant is the arrangement of the flowering branches, and of the flowers upon them. An Inflorescence is a flowering bi'anch, or the flower- ing summit of a plant above the last stem-leaves, with its branches, bracts, and flowers. . A single flower, or an inflorescence, is terminal when at the summit of a stem or leafy branch, axillarii when in the axil of a stem-leaf, leaf-opposed when opposite to a stem-leaf. The inflorescence of a plant is said to be terminal or determinate when the main stem and principal branches end in a flower or inflorescence (not in a leaf- bud), axillary or indeterminate when all the flowers or inflorescences are axillary, the stem or branches ending in leaf-buds. . A Peduncle is the stalk of a sohtary flower, or of an inflorescence ; that is to say, the portion of the flowering branch from the last stem-leaf to the flower, or to the first ramification of the inflorescence, or even up to its last ramifications ; but the portion extending from the first to the last ramifications or the axis of inflorescence is often distinguished under the name of rhacJds. . A Scape or radical Peduncle is a leafless peduncle proceeding from the stock, or from near the base of the stem, or apparently from the root itself. . A Pedicel is the last branch of an inflorescence, supporting a single flower. . The branches of inflorescences may be, like those of stems, opposite, alternate, etc. (32, 33), but very often thefr arrangement is diff'erent from that of the leafy branches of the same plant. . Inflorescence is centrifugal, when the terminal flower opens first, and those on the lateral branches are successively developed. centripetal, when the lowest flowers open first, and the main stem continues to elongate, developing fresh flowers, . Determinate inflorescence is usually centrifugal. Indeterminate inflorescence is always centripetal. Both inflorescences may be combined on one plant, for it often happens that the main branches of an inflorescence are centripetal, whilst the flowers on the lateral branches are centrifugal ; or vice versa. . An Inflorescence is a SpiTce, or spicate, when the flowers are sessile along a simple undivided axis or rhachis. a Raceme, or racemose, when the flowers are borne on pedicels along a single un- divided axis or rhachis.