Botany of the Southern states . xplicable were not the ovaries examined in their earlieststate. A one-celled ovary becomes a two or more celled fruit:in the Cruciferae by the enlargement of the placenta; in theAstragalus by the expansion of the suture; in other cases bythe dilations of the lining of the pericarps, which form horizon-tal dissepiments. The Pomegranate presents a remarkablevariation from the true type. 150. When the fruit arrives at maturity, the j^ericarp eitherbursts or it remains closed; if the latter, it is said to be inde-hiscent, as in the apple, hazel-nut, &c. If it bursts
Botany of the Southern states . xplicable were not the ovaries examined in their earlieststate. A one-celled ovary becomes a two or more celled fruit:in the Cruciferae by the enlargement of the placenta; in theAstragalus by the expansion of the suture; in other cases bythe dilations of the lining of the pericarps, which form horizon-tal dissepiments. The Pomegranate presents a remarkablevariation from the true type. 150. When the fruit arrives at maturity, the j^ericarp eitherbursts or it remains closed; if the latter, it is said to be inde-hiscent, as in the apple, hazel-nut, &c. If it bursts, it is said tobe dehiscent, and it follows invariably the same course in thesame species; hence it is important to notice the varieties. Insome cases the dehiscence takes place by dividing the dissepi-ments, that is, the carpels separate into their original leaves, asin the Delphinium, and this is called septicidal dehiscence. represents this kind, in which a represents the axis, d the Fig. 140. Fig. 141. Fig. dissepiment, and v the valves. In other cases the dissepimentsare attached to the middle of the valves, and the dehiscence insuch cases, no doubt, takes place at the midrib of the leavesthat form the carpels. This is called loculicidal dehiscence, as 149. How many ovules in the chestnut? How many perfected ? Howin the oak? When does the reverse take place?—150. When is the fruitsaid to be indehiscent? When dehiscent ? When is the dehiscence sep-ticidal? When loculicidal? 88 FRUIT. in the Lilac, Gladiolus, &c. (Fig. 141.) Septifragal dehiscenceis when the dissepiments separate from the valves, but adhereto the axis, as in the Convolvulus. (Fig. 142.) In sutural de-hiscence there is but one carpel, and of course no true dissepi-ments, as in the Pea and Bean. The circumscissile dehiscenceoccurs by a transverse separation of the valves half round thepericarp, as in the Anagallis. This is an uncommon Plantago has a transverse dehiscence. Besides the a
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