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form tassels of greater or less extent. Here it is the 

 mother cell destined normally to close the circuits with a 

 pointed growth, which in plants thus affected fails to do 

 so, and proceeds instead to split up and form more or less 

 numerous supplementary growths to, in extreme cases, an 

 unlimited extent. Such an instance we have witnessed 

 in a tasselled form of Pferis sevvulata, one point of which 

 survived the winter, and in the following season began to 

 fork and fork again dichotomously, until eventually a huge 

 bunch, as large as one's fist, resulted. As a rule, however, 

 the multiplication is lim.ited by the cessation of fresh 

 division, the tassel being clearly complete when the 

 terminal is fully uncoiled. 



A peculiarity of this phenomenon is that, judging by the 

 innumerable instances in which it has appeared both 

 under cultivation and under wild conditions, every genus 

 and species would appear to be subject to it, although, 

 singular to relate, so far, we believe, no fossil fern has 

 been found so characterised, and certamly it does not 

 present itself in any case as a specific feature. We 

 cannot, of course, assert that all ferns are subject to vary 

 in this way, but the fact remains that whenever a species 

 becomes largely propagated for trade purposes, sooner 

 or later tasselled forms arise from the spores, and these 

 inherit the capacity of producing the same type of off- 

 spring, generally on such lines as permits of selective 

 culture involving further development of character. It 

 may be thought that the phenomenon of fasciation, not 

 uncommon in phanerogamous plants, is identical with this, 

 but it is not. With fasciated plants we find it is true that 

 the mother cells multiply on abnormal lines, but they do 

 this usually, if not always, at an incipient state of growth, 

 so as to increase the number of stalks or stems which at 

 first grow together, but may subsequently separate to give 

 room to sidegrowths on as near normal lines as space 



