Page:An introduction to physiological and systematical botany (1st edition).djvu/465

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DIDYNAMIA.
435

Lamium has the mouth toothed on each side, t. 768.

Prunella, t. 961, has forked filaments; Cleonia 4 stigmas; Prasium a pulpy coat to its seeds. These instances will suffice as clear examples of natural genera, distinguished by an essential technical character, in a most natural order.

2. Angiospermia. Seeds in a capsule, and generally very numerous. The plants of this order have the greatest possible affinity with some families in Pentandria Monogynia. Some species even vary from one class to the other, as Bignonia radicans, Curt. Mag. t. 485, and Antirrhinum Linaria, Engl. Bot. t. 653, 260, in which the irregular corolla becomes regular, and the 4 unequal stamens are changed to 5 equal ones; nor does this depend, as has been asserted, on the action of any extraneous pollen upon the stigmas of the parent plant, neither are the seeds always abortive. No method of arrangement, natural or artificial, could provide against such anomalies as these, and therefore imperfections must be expected in every system.