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question. In looking over the literature of this subject so far as 

 it is available I find that most of the ferns which have been des- 

 cribed as hybrids are mere crosses between varietal forms of 

 some one species, and therefore are not true hybrids. Much of 

 this will depend of course upon one's judgment ; some authors re- 

 garding as good species what others may consider as mere 

 varieties. But I believe that the actual number of ferns that 

 have apparently originated from the crossing of species whose 

 distinctiveness is recognized by all can be counted upon one's 

 fingers. 



One of the most recent and best of these is the New England 

 hybrid Aspidiujn cristatumxmarginale (Davenport) discovered 

 by Raynal Dodge, of Newburyport. I have had seveial plants of 

 this fern growing under my immediate observation for the past 

 four years and I can find no reason for changing the views which 

 I expressed when I first published it; but I find as my plants be- 

 come older they change considerably in their appearance. This 

 year some of the plants look quite different from what they did 

 last year, the lower portion of the largest fronds suggesting 

 Clintonianum more than cristatum, while some Medford plants 

 that resembled a lax form of Clintonianum when found have be- 

 come more compact and like the others; but in all, the essential 

 characters remain, and these are, the broad marginale-\\ke 

 upper portion of the frond with acuminate pinnae and cristatum 

 fruit; the narrower cristatum-Wke lower portion, the marginale 

 scales and above all the erect candex with dense central crown. 



One of the most striking characteristics is its proneness to 

 develop abortive fronds. Some plants exhibit this tendency more 

 than others, but the most perfect plant I have and which has 

 matured perfect fronds up to August ist, has during the past 

 three weeks been developing secondary fronds of an abortive 

 character, and this tendency I believe to be one of the strongest 

 characteristics of hybrid ferns. 



But I have already made my paper too long, and I will close 

 by expressing the hope that those of you who can will experiment 

 with spore sowing and record the results. It will not be neces- 

 sary for you to go into any scientific microscopical work to do 

 this, as the process is simple and there is plenty of material avail- 

 able. A shallow flower pot well drained, and filled with a light 

 porous soil, well sterilized, and watered is all you need. Sow the 

 spores on the damp surface, set the pot in a pan of water and 



