. Lessons with plants. Suggestions for seeing and interpreting some of the common forms of vegetation. he base) a simple inflorescence is a raceme. 216(1. The lily-of-the-valley (Pig. 184) is a typicalexample of a raceme. The leaves are reduced to merebracts. The currant (Fig. 185) is also a, good example. 217. If the pedicels in a raceme wereobsolete, and if the flowers were close to-gether, we should have a typical spike. 217«r. The common plantain of door-yards () bears its flowers in a spike. In such long spikesthere is usually a gradual progression in anthesis (inthe o
. Lessons with plants. Suggestions for seeing and interpreting some of the common forms of vegetation. he base) a simple inflorescence is a raceme. 216(1. The lily-of-the-valley (Pig. 184) is a typicalexample of a raceme. The leaves are reduced to merebracts. The currant (Fig. 185) is also a, good example. 217. If the pedicels in a raceme wereobsolete, and if the flowers were close to-gether, we should have a typical spike. 217«r. The common plantain of door-yards () bears its flowers in a spike. In such long spikesthere is usually a gradual progression in anthesis (inthe opening of the flowers) from below upwards, so thatthe spike is not in bloom simultaneously throughoutits length. The lowest flowers often wither and die, as Pig. 186. Spike ofplantain. 190 LSSSONS WITS PLANTS in the plantain, while the middle flowers are still in bloom. Specialkinds of spikes, as we have found, are the spadix and the much-condensed — much-shortened — spike is called a head. 218. If the lowest pedicels of the raceme wereelongated (or the upper ones remained shortened). Fig. of a last years umbel of wild carrot. SO that the cluster were convex or nearly flaton top, we should have a corymb. That is, acorymb is an expanded cluster, in which theoutermost flowers open first. 219. If the axis of the corymb were so verymuch shortened that all the pedicels seem to startfrom the same point, like the rays of an invertedumbrella, we should have an umbel. 219a. Umbels are characteristic of the plants of the parsleytribe, as parsnip, caraway, dill, celery, carrot and coriander. Often THE ABBAN6EMENT OF THE FLOWERS 191 the umbel is compound; that is, secondary umbels, or umbellets,are borne on the ends of the rays (as the pedicels of an umbel areoften called). The bracts which subtend the pedicels in the racemeand corymb become verticillate under the umbel, or form an in-volucre; and the umbellets may be pro-vided with involucels. A last years umbelo
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Keywords: ., bookauthorbai, bookcentury1900, bookdecade1900, booksubjectbotany
