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BRIEFER ARTICLES. 
FERN VARIATION IN GREAT BRITAIN. 
Up to a comparatively recent date, the departures from the normal 
type of ferns which were found growing wild under perfectly natural 
conditions received little or no attention from professional botanists, 
but were simply dubbed “ monstrosities” and left to amateurs to collect, 
cultivate, and observe. Eventually, however, the discovery that these 
“sports” did not always merely involve a superficial change of form, 
but also that this change was in some cases correlated with hitherto 
unknown modifications and abridgments of the normal life cycle, led 
to a greater interest being taken, with the result that theories as to the 
origin of alternation of generations were seriously affected. Before 
these investigations and discoveries, it was assumed that the life cycle 
was necessarily spore, prothallus, fertilized egg, and finally the sporo- 
phyte or fern proper. Apogamy, however, discovered by Professor 
Farlow, eliminated the sexual act, a vascular structure originating in 
the prothallus which resulted in an asexual bud, whence at once arose 
the sporophyte, the life cycle then being spore, prothallus, sporophyte. 
This, though first remarked in a normal Preris cretica, was subsequently 
found by DeBary to occur with seeming constancy in an abnormal 
tasselled form of Lastrea (Z. pseudo-mas cristata) and several other 
species normal and abnormal. The next discovery was that of soral 
apospory by the writer, on a form of Athyrium filix-foemina, which 
shortened the life cycle in another way altogether, by eliminating the 
Spore, inasses of prothalli being produced, as Professor F. O. Bower 
subsequently ascertained, from the stalks of aborted sporangia, on the 
ordinary soral sites... Here the life cycle runs thus, sporophyte, sorus, 
prothallus, fertilized egg,sporophyte. No sooner was this phenomenon 
announced than Mr. G. B. Wollaston reported the still more remarkable 
case of apical apospory ina form of Polystichum angulare (P. ang. 
pulcherrimum), in which the abnormally long sickle-shaped pinnules 
*DRUERY, C. T.: Jour. Linn. Soc. 21: 354. 1884; 22:427-440. 1885. Bower, 
F. O.: Trans. Linn. Soc. 2: 301-326. 1887. 
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