The fronds in the whole series are generally green, ex cept in the under surface, which is white in one ?icrostichum and in Cyathea dealbata, and other species, whilst it is of a beautiful yellow in .9crostichum sulphuream.
The young buds both of the stem and fronds, are often beset with scales or hairs, and sometimes this is the case with the under part of the expanded fronds. It is singular, that Hedwig should have mistaken these hairs in the infant :fronds for anther? ; so very apt are men of the first talents to hunt after analogies where none can possibly exist.
If we except the magnificent palms, no plants are really mole ornamental than ferns. To them, indeed, we are not attracted by the fine colour or perfume of the flower ; but, even in our northern climate, there is a peculiar freshness and beauty in the bright green hue of the arched frond and elegantly divided pinnulx of the Brake and Polypody. No plants are better adapted than these to adorn the sloping bank of the clear and pebbly stream ; and their beauty in such situations has not been overlooked by the fine taste of one t.f the first poets of our time : The number of ramifications of the vascular fasciculi differs greatly in the numerous species. In the P. anreum, a single branch turns at a right angle into the pinnulx ; whereas in the more complicated frond of Davallia cane riensis, and others of a like form, several ramifications ac company the respective subdivisions of the frond ; and to wards the end of autumn, in our native species, a skeleton of the ligneous fasciculi can be dissected from the surround ing cellular matter, through the minute ramifications of the frond, almost to their apparent termination in the groups of capsules. In several species, these vessels swell at their extremity into knobs ; a circumstance that gave rise to the hypothesis of Bernhardi, who supposed them to be the male organs ;* but, unfortunately for this hypothesis, it has since been observed by Sprengel, that the supposed organs are wanting in many species; but where they do exist, be admits that the minute vermicular bodies contain ed within them are probably receptacles of the concentra ted juices of the veins, which, according to his own hypo thesis, perform the chief part in the process of fecundation.
Other parts in the frond have, however, by various wri ters, been supposed to perform this important function.
Michell, whose accuracy in other respects is well known, attributed the office of antherx to the capillary productions, which he discovered on the unevolved fronds; and, as alrea dy observed, Hedwig adopted and illustrated this opinion, (Theoria Gen. Pl. Crypt. tab. v. vii.) Gleichen consider ed these organs to be situated in those minute fissures, on the lower surface of the cuticle of the frond, which are well illustrated by Sprengel (T. ii. fig. 14.) in his work on cryptugamous plants ; whilst Kolreuter assigned this of fice to that production of the cuticle of the frond, which, in most of the tribes of ferns, forms the involucrum of the groups of capsules. But leaving these various hypotheses to their natural fate, it is full time to proceed to the consi deration of the capsules themselves.
The singular aspect of these plants, which every one ob served to spring up in wild and uncultivated places, without any visible seeds, seems to have given rise, in an age of ge neral ignorance, to those superstitious fancies formerly prevalent in several parts of Europe. It was a practice among the people to collect the capsules, which they consi dered as the seeds of ferns, on midsummer eve, and make use of them in various charms. " We have the receipt of fern seed," says Gadshill, in Shakspeare's Henry IV. we walk invisible." In fact, the botanists of the sixteenth century partook in the faith of the times. Valerius Cordus, in his commentaries on Dioscorides, 'Tagus, and Baptista Porta, ignorant of the existence of the capsules, all agreed, that the powder found on the lower part of the frond produ ced plants. Cordus, however, contended, like some of the . time, that this powder could not be true seed, be cause the plants were destitute of flowers; and although Morison long afterward (Hist. P1. Y. iii. sect. xiv. p. 593.) observed and described the germinating plants of the Os munda regalis, it is clear that he was unacquainted with the seeds being contained in capsules. It is singular, that Mal pighi (.gnat. Plant. p. 72. tab. 51) Grew, (?That. of Plant. tab. 62) and Swammerdam, (Bibl. ?Vat.) should have disco vered the true nature of the fruit nearly at the same period.