. Introduction to structural and systematic botany, and vegetable physiology. Botany. CHOKISIS OR DEDUPLICATION. 243 454. Choiisis or Dcduplication, The name dedouhlement of Dunal, which has been translated deduplication, literally means unlining ; the original hypothesis being, that the organs in question unline, or tend to separate into two or more layers, each having the same structure. We may employ the word deduplication, in the sense of the doubling or multiplication of the number of parts, without adopting tins hypothesis as to the nature of the process, which at best can well apply onl
. Introduction to structural and systematic botany, and vegetable physiology. Botany. CHOKISIS OR DEDUPLICATION. 243 454. Choiisis or Dcduplication, The name dedouhlement of Dunal, which has been translated deduplication, literally means unlining ; the original hypothesis being, that the organs in question unline, or tend to separate into two or more layers, each having the same structure. We may employ the word deduplication, in the sense of the doubling or multiplication of the number of parts, without adopting tins hypothesis as to the nature of the process, which at best can well apply only to some special cases. The word chorisis .(xa>p""f, the act or state of separation or multiplication), also pro- posed by Dunal, does not involve any such assumption, and is ac- cordingly to be preferred. By regular multiplication, therefore, we mean the augmentation of the number of organs through the de- velopment of additional circles ; which does not alter the symmetry of the flower. By chorisis we denote the production of two or more organs in the place of one, in a mai?ner analogous to the division of the blade of a leaf into a number of separate blades, or leaflets. 455. Chorisis, or the division of an oi'gan into a pair or a cluster, may take place in two ways. In one case the parts or organs thus produced stand one before the other ; in the other case they stand side by side. The first is named transverse chorisis ; the second, collateral chorisis. Both must evidently disturb or disguise the normal symmetry of the blossom. 456. Collateral Chorisis is that in respect to which there is least doubt as to the nature of the process. We have a good example of it in the tetradynamous stamens (519) of the Mustard or Cress family (Fig. 406). Here, in a flower with a symmetrical tetramerous calyx and corolla, we have six stamens ; of which the two lateral or shorter ones are alternate with the adjacent l^etals, as they normally should be, while the four are in two
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