Page:An introduction to physiological and systematical botany (1st edition).djvu/516

 486 hand, according to the principle I have suggested, of retaining in them such genera only as have a permanent difference in the accessory as well as the essential parts of their flowers, their bulk being by such a reformation much diminished, it might be advisable to reduce them to one Class, in which the slender remains of Polygamia might commodiously be included, and the title of such a Class should be Diclinia, expressing the two distinct seats or stations of the organs of fructification.

24. Cryptogamia. Stamens and Pistils either not well ascertained, or not to be numbered with any certainty. Orders 5.

1. Filices. Ferns. The parts of their flowers are almost entirely unknown. The fructification, taken collectively, and proved to be such by the production of prolific seeds, grows either on the back, summit, or near the base of the frond. Some are called annulatæ, annulated, their capsules being bound with an elastic transverse ring; others thecatæ, or more properly exannulatæ, from the want of such an appendage,