10 



INTRODUCTION. 



said to be textile when it has no peduncle i. e., when it is seated close 

 to the stem of the plant. 



4:1). The leaves of a flower cluster are usually very much reduced in 

 form- often mere scales. They are then called bracts when on the 

 petiole, and when on its branches, bractlets. In a broader sense 

 bract '' refers to both forms. Sometimes the bracts are wanting alto- 

 u'ether. In case a ilower appears in each axil of leaves which regularly 

 develop, thev are not spoken of as forming a flower-cluster, but are said 

 to be solitary and axillary. 



50. An Indeterminate Inflorescence is the one formed when the 

 flowers appear from axillary buds, while the terminal bud continues 

 developing leaves and prolonging indefinitely the common axis. In this 

 form the blossoming commences below and progresses upward is said 

 to be axcendintj the older buds developing their flowers first, and in 

 case 1 their pedicels are considerably prolonged, so as to make a broad 

 flat flower-cluster, the outer flowers develop before the central ones. 



From that fact the inflorescence is said to be centripetal. 



51. The principal forms of the 

 Indeterminate Inflorescence are the 

 following: 



52. .1 Raceme, when the flowers 

 are arranged singly along a common 

 axis, and furnished with pedicels of 

 about equal length. (Fig. 21.) 

 Sometimes the buds along the axis, 

 instead of developing single flowers, 

 develop little racemes of flowers, when 

 the whole cluster is spoken of as a 

 compound raceme. When rather 



irregularly compound, as in the Oatalpa, Oat, etc., it is spoken of as a 

 panicle, and a compact pyramidal form of this, as presented by the 

 flower-cluster of the Horse-chestnut or a bunch of grapes, is called a 

 thyrsus. 



53. A Corymb differs from a raceme 

 in having the lower pedicles longer, so as 

 to raise their flowers nearly or quite to 

 the level of the uppermost. (Fig. 22.) 



54. An Umbel is a cluster where the 

 pedicels are all prolonged, and grow all 

 from the summit of the peduncle. (Fig. 

 23.) They are here called rat/x, and are 

 often subtended by a whorl of bracts, 

 called an involucre. In the compound 

 umbel each ray supports, instead of a 

 single flower, a little umbel, called an 

 nmbelJet, and its whorl of bracts if there be one 



55. A Sj)ikf. differs from a raceme in that the flowers have, no pedicels 

 i. e., they are sessile along the axis of inflorescence, which is here 



>f as the ravlds. (Fig- 2-1.) A. pendent, spike, as seen 



Figs, iil-ii-i. Forms of Indeterminate Inflorescence. 



Corymb. 



Fio. 22. 



