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of, as is unfortunately far too much the case, leaving 

 C. T. D. to do nearly all the work, thus to that extent 

 reaping the benefit of a single brain only instead of the 

 brains of a community. 



The Editor. 



HOW FERNS DEVELOP. 



At this season of the year, when the Ferns are resuming 

 active growth after the long winter's rest, it is most inter- 

 esting to go round one's collection and note how the various 

 species behave as regards the lifting and unfolding of their 

 new fronds. One and all of course, save the little Adders- 

 tongue and Moonwort, which are probably absent as they 

 do not rank with the elite or decorative section, produce 

 their fronds on circinate or coiled up lines and develop 

 them by a constant uncoiling of the frond and its segments, 

 and their subsequent expansion and flattening out. This 

 feature distinguishes the Ferns generally from the flower- 

 ing plants, and the mode in which it commences, and which 

 commencement is usually concealed within the inmost 

 recesses of a scaly crown, is extremely interesting. In the 

 very centre of a crown-forming fern, such as the Lastreas 

 and Polystichums, each frond begins with what is termed 

 a mother cell. This cell multiplies itself on such lines that 

 a knob is produced, consisting of an embryo coil, with its 

 top rolled inwards towards the centre. A series of such 

 knobs is arranged circularly all pointing inwards and 

 covered by more or less dense scales, which are best seen 

 in the Lastrea and Shield Ferns. These eventually form 

 a closely packed mass, which may be formed long before 

 the spring growth begins and lies quite dormant until it 

 does. When growth is resumed, it is the tightly inrolled 

 coils constituting the knobs which commence to multiply 

 the cells at the tips and to build up an embryo main stalk 

 and the subsidiary stalks of the divisions and subdivisions, 



