. Lessons with plants. Suggestions for seeing and interpreting some of the common forms of vegetation. acase (Figs. 136, 137). The willow is also peculiarin the fact that the flowers are borne in a denseelongated scaly cluster. Such clusters of flowersare called aments or catkins. 176a. It is customary to speak of staminate and pistillate plants astwo sexes; but sex in plants may not be comparable with sex in animals. DICLINOUS FLO WEBS 157 177. The staminate catkin of one of the birchesis shown in Fig. 155. This is a drooping body,and recalls the similar tassels of the poplars,oaks, and hazel
. Lessons with plants. Suggestions for seeing and interpreting some of the common forms of vegetation. acase (Figs. 136, 137). The willow is also peculiarin the fact that the flowers are borne in a denseelongated scaly cluster. Such clusters of flowersare called aments or catkins. 176a. It is customary to speak of staminate and pistillate plants astwo sexes; but sex in plants may not be comparable with sex in animals. DICLINOUS FLO WEBS 157 177. The staminate catkin of one of the birchesis shown in Fig. 155. This is a drooping body,and recalls the similar tassels of the poplars,oaks, and hazels. Inthis instance, however,there is more than asingle flower beneatheach scale of the cat-kin. In other words,a catkin may be eithersimple (comprising asingle flower at eachjoint or under each^.scale) or compound. 177a. There are commonlythree beneath each externalscale in the birch, each flowercomprising two stamens, butthe anther loeules are separatedand the filaments divided soas to imitate four stamens. These flowers are separately ^ ^^® subtended by braetlets. Pistillate catkin of a 178. The pistillate catkin of another kind ofbirch is shown in Fig. 156. It is a rigid or erectstructure, and, of course, persists until the seedsare ripe, whereas the entire staminate catkin verysoon dies and falls. One of the three-parted bractsor scales is removed and reversed at a. It sub- 158 CSSSONS WITff PLANTS tends three naked pistils, each having two stylesand being provided with a broad wing. It isseen, therefore, that staminate and pistillate catkins
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Keywords: ., bookauthorbai, bookcentury1900, bookdecade1900, booksubjectbotany
