The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . so that the flowers are sessile, a spike is pro-duced, as in Plantago and Verbena ofiicinalis (fig. 160).The spike sometimes bears unisexual flowers, usuallystaminiferous, the whole falling oflf by an articulation, asin Willow or Hazel (fig. 161), and then it is called anamentum or catkin, hence such trees are called amenti-ferous; at other times it becomes succulent, bearing numer-ous flowers, surrounded by a sheathing bract or spathe,and then it constitutes-a spadix, which may be simple, asin Arum macula
The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . so that the flowers are sessile, a spike is pro-duced, as in Plantago and Verbena ofiicinalis (fig. 160).The spike sometimes bears unisexual flowers, usuallystaminiferous, the whole falling oflf by an articulation, asin Willow or Hazel (fig. 161), and then it is called anamentum or catkin, hence such trees are called amenti-ferous; at other times it becomes succulent, bearing numer-ous flowers, surrounded by a sheathing bract or spathe,and then it constitutes-a spadix, which may be simple, asin Arum maculatum (fig. 153), or branching, as in spike bearing female flowers only, and covered withscales, is either a sirobilus, as in the Hop ; or a cone, as inthe Fir (fig. 133). It may be mentioned here that manydo not consider the cone of Eirs an axis of inflorescence, POEJIS OF mFLOKESCENCE.] BOTANY 12y but regard it as a single flower with tho floral leaves placedat difcrcnt heights. In Grasses there are usually numerousfioasilo flowers arranged in small spikes, called locustce or. Fig. 159. Fig. 160. Fig. 161. r 0. 159.—Corymb of Cerasus Mahaleb, produced in the axil of a which hasalien, and terminiting an abortive ijranch, at the base of wliich are in the form of scales, e. FO. leO.^^pilce of Verbma q^cinalis, showing sessile flowers on a commonrachis. The flowers at the lower part of the spike have passed into fruit,those towardB the middle are in full bloom, and those at the top are only iAbud. Pig. 161.—Amentum or catkin of Hazel (Coryliis AvcUana), consisting of an axisor rachis covered with bracts in the form of scales (squamcE^ each of whichcovers a male flower, the stamens of which are seen projecting beyond the catkin falls off ia a mass, separating from the branch by an articulation. spikelets, which are either set closely along S central axis,or produced on secondary axes formed by the branchingof the central one j to the latte
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectencyclo, bookyear1902
