The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . Fig. of Mallow iMatva tt/hctti-tti. similar inflorescence is seen in Xylophylla longifolia. Whenthe axes become very much shortened, the arrangcpient ismore complicated in appearance, and the nature of the in-florescence can only be recognized by the order of opening ofthe flowers. In Labiate plants, as the Dead-nettle (Lami\im),the flowers are produced in the axil of each of the foliageleaves of the plant, and they appear as if arranged in asimple whorl of flowers. But on examination it is fo
The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . Fig. of Mallow iMatva tt/hctti-tti. similar inflorescence is seen in Xylophylla longifolia. Whenthe axes become very much shortened, the arrangcpient ismore complicated in appearance, and the nature of the in-florescence can only be recognized by the order of opening ofthe flowers. In Labiate plants, as the Dead-nettle (Lami\im),the flowers are produced in the axil of each of the foliageleaves of the plant, and they appear as if arranged in asimple whorl of flowers. But on examination it is foundthat there is a central fluwer expanding first, and from its axis two secondary axes spring bearing solitary flowers ; tlieexpansion is thus centrifugal. The inflorescence is there-fore a contracted dichasium, the flowers being sessile, otnearly bo, and the clusters are called vcrltcillasUrs (fig. 107).. Fig. 107. lowering stalk of the WTiIto Dead-nettle, (L<jmium alhutn) The bracts K ftpro like the ordinary leaves of tho plant, and produce clusters of flowers In theiraxil. Ttin clusters aro called Terticlllaaters. and consist of flowers which axeproduced In a centrifugal manner. Sometimes, especially towards the summit of a dichasium,owing to the exhaustion of the growing power of the plant,only one of the bracts gives origin to a new axis, the otherremaining empty ; thus the inflorescence becomes unilateral,and further developinent is arrested. In addition to thodichasial form there are others where more than two lateralaxes are produced from the primary floral axis, eadh ofwhich in turn produces numerous axes. To this form theterms irichotomous and polytomous cyme have been applied ;but these are now usually designated cymose umbels. Theyare well seen in some species of Euphorbia. Another term,anthcla, has been used to distinguish such forms as occurin several species of Luzula
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