CHAPTER. I. 
THE LIFE-HISTORY OF A FERN. 
Tne middle years of the nineteenth century marked an important epoch 
in the history of Plant Morphology. Before that period this branch of 
botany could hardly be said to exist as a science. What gave distinction 
to that period was the publication of observations which made it possible 
for the first time to give a consecutive account of the various stages in 
the life-history of the Higher Cryptogamia. Up to that time it had been 
the custom to compare Ferns with Flowering Plants, notwithstanding that 
the facts, so far as they were known, gave little support to any view of 
their close similarity; and to attempt to express the life-story of these 
and others of the lower plants in terms of the higher. But the investigations 
of that period, by following out the actual facts of development, showed 
not only that there was no correlative of the seed in the life-cycle of a 
Fern, but also that there was in the prothallus of Ferns a phase of the 
life-cycle which differed in essential pointg from anything which was then 
known to exist in the development of Seed-Plants. 
The spores of Ferns were experimentally recognised as reproductive 
organs by Morison (1699), who raised young plants from them. But Kaulfuss 
first observed their germination (1825), and the formation of the prothallus, 
which had already been described by Ehrhart (1788): it was Bischoff (1842) 
who first recognised the embryo attached to the prothallus. Naegeli (1844) 
discovered the antheridia and spermatozoids, while Suminski (1848) 
ascertained the true nature of the archegonium, and its relation to the 
embryo. But it remained for Hofmeister to put together, and complete 
the story. In 1849 his description of the germination of Pilwlarca and 
Salvinia appeared, and two years later, in 1851, he gave to the world his 
Vergleichende Untersuchungen, a work which dealt in the most com- 
prehensive way with the life-story of a number of Liverworts, Mosses, 
Ferns, Fern-Allies, and Gymnosperms. 
It is impossible to exaggerate the importance of the advance in view 
which the publication of Hofmeister’s book brought. The middle years 
