Page:Parsons How to Know the Ferns 7th ed.djvu/65

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HOW TO USE THE BOOK

both a fertile and a sterile frond. In carrying them home you will remember the necessity of keeping together the fronds which belong to the same plant.

When sorting your finds you will group them according to the Guide. The broad-leaved Sensitive Fern, with its separate, dark-green fruit cluster, makes its way necessarily to Group I. To Group II goes your pale-fronded Royal Fern, tipped with brown sporangia. As a matter of course you lay in Group III the leaf-like but dissimilar sterile and fertile fronds of the Slender Cliff Brake. The spreading Brake, its reflexed margin covering the sporangia, identifies itself with Group IV. The oblong fruit-dots of the little Mountain Spleenwort carry it to Group V, while the round ones, like pinheads, of the Evergreen Wood Fern announce it a member of Group VI.

The different ferns sorted, it will be a simple matter to run quickly through the brief descriptions under the different Groups till you are referred to the descriptions in the body of the book of the species under investigation.

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