. Introduction to structural and systematic botany, and vegetable physiology. Botany. DETERMINATE INFLORESCENCE. 217 and more or less elongated inflorescence which is irregtdarly branched twice, thrice, or a greater number of times. 400. A Thyrsus, or Thyrsc, is a compact panicle of a pyramidal, ovaly or oblong outline ; such as the cluster of flowers of the Lilac and Horsechestnut, a bunch of grapes, &c. 401. Definite or Determinate Inflorescence. In this class, the flowers all represent terminal buds (380). The primary axis is directly terminated by a single flower-bud, as in Fig. 327, a
. Introduction to structural and systematic botany, and vegetable physiology. Botany. DETERMINATE INFLORESCENCE. 217 and more or less elongated inflorescence which is irregtdarly branched twice, thrice, or a greater number of times. 400. A Thyrsus, or Thyrsc, is a compact panicle of a pyramidal, ovaly or oblong outline ; such as the cluster of flowers of the Lilac and Horsechestnut, a bunch of grapes, &c. 401. Definite or Determinate Inflorescence. In this class, the flowers all represent terminal buds (380). The primary axis is directly terminated by a single flower-bud, as in Fig. 327, and its growth is of course arrested. Here we have a solitary terminal flower. Further growth can take place only by the development of secondary axes from axillary buds. These may develop at once as peduncles, or as leafy branches ; but tliey ai-e in either case arrested, sooner or later, by a flower-bud, just as the primary axis was (Fig. 328). If further development ensues, it is by the production of branches of the third order, from the axils of leaves or bracts on the branches of the second order (Fig. 329) ; and so on. Hence this mode of inflo- rescence is said to be definite or determinate, in contradistinction to the indeterminate mode, already treated of, where the primary or leading axes elongate indefinitely, or merely cease to grow from the failure of nourishment, or some other extrinsic cause. The most common and most regular cases of determinate inflorescence occur in opposite-leaved plants, for obvious reasons; and such are accordingly chosen for the subjoined illustrations. But the Kose, Potentilla, and Buttercup furnish familiar examples of the kind in alternate-leaved Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Gray, Asa, 1810-1888. New York [etc. ] Ivison, Blakeman, Taylor &
Size: 1720px × 1453px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorgra, bookcentury1800, bookdecade1850, booksubjectbotany
