. Our ferns in their haunts; a guide to all the native species. Ferns. THE UNCOILING FRONDS. 17 fern. Instead, there appears a peculiar flat, green, heart- shaped body, scarcely a quarter of an inch across, known 2,% t\iQ prothalliiim. On the underside of this are borne two sets of organs and finally by a union of their contents, a new fern is produced. It is small wonder that this complicated process was so long a puzzle to investigators of plants. The knowledge of the subject grew very slowly. In 1648 the nature of the sporangia was first made out, and in 1669 the spores themselves were dis-
. Our ferns in their haunts; a guide to all the native species. Ferns. THE UNCOILING FRONDS. 17 fern. Instead, there appears a peculiar flat, green, heart- shaped body, scarcely a quarter of an inch across, known 2,% t\iQ prothalliiim. On the underside of this are borne two sets of organs and finally by a union of their contents, a new fern is produced. It is small wonder that this complicated process was so long a puzzle to investigators of plants. The knowledge of the subject grew very slowly. In 1648 the nature of the sporangia was first made out, and in 1669 the spores themselves were dis- covered. In 1715 Morrison is said to have raised young plants from spores but it was not until 1788 that the office of the prothallium was known and more than thirty years later before its development was observed. Lastly it was not until near the middle of the nineteenth century that the functions of the small organs on the prothallium were discovered. The time required for a fern to come to maturity from the spore is from three to seven years. As may be imagined, many dan- gers threaten the young sporeling, and some species have devised vari- ous " short-cuts" by which to avoid the perils that often seem to threaten the very existence of their race. One of the bladder ferns produces spores in abundance and in addition, little bulblets grow from the under surface of the fronds. The spores , . , ^ SOEI OF POLYPODIUM. are scattered far and wide and may or may not land in a favourable place for germi- nation, but the bulblets drop into the soil beside their parents, ready to form new plants. It is interesting to know that the first fronds from these bulblets are much. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Clute, Willard Nelson, b. 1869. New York, F. A. Stokes Co
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishernewyo, bookyear1901
