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236, 237). Some capsules are of one locule, but they may have been compound when young (in the ovary stage) and the partitions may have vanished. Sometimes one or more of the carpels are uniformly crowded out by the exclusive growth of other carpels (Fig. 235). The seeds or parts which are crowded out are said to be aborted.

Fig. 234.—Capsule of Morning Glory.

Fig. 235.—Three-carpeled Fruit of Horse-chestnut. Two locules are closing by abortion of the ovules.

There are several ways in which capsules dehisce or open. When they break along the partitions (or septa), the mode is known as septicidal dehiscence (Fig. 236); In septicidal dehiscence the fruit separates into parts representing the original carpels. These carpels may still be entire, and they then dehisce individually, usually along the inner edge as if they were follicles. When the compartments split in the middle, between the partitions, the mode is loculicidal dehiscence (Fig. 237). In some cases the dehiscence is at the top, when it is said to be apical (although several modes of dehiscence are here included). When the whole top comes off, as in purslane and garden portulaca (Fig. 238), the pod is known as a pyxis. In some cases apical dehiscence is by means of a hole or clefts.

Fig. 236.—St. John's Wort. Septicidal.

Fig. 237.—Loculicidal Pod of Day-lily.

The peculiar capsule of the mustard family, or Cruci-