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THE AMERICAN NATURALIST 



[Vol. XLI 



ceros — be true. This hypothesis assumes that, by the develop- 

 ment of a root from the lower part of the sporophyte and a 

 complete septation of the sporogenous tissue of the sporogonium 

 so that something resembling the spike of an Ophioglossum 

 resulted, there would be formed a plant not very unlike O. sim- 

 plex. We actually have in the embryo sporophyte of 0. moluc- 

 canum a plant which consists simply of leaf and root. Of course 

 the leaf is not sporogenous, but the ancestral forni must have 

 developed a sporogenous structure comparable to the spike before 

 the foliage leaf arose. The latter presumably was formed as a 

 lateral outgrowth of the sporogenous portion, as there seems to 

 be some evidence is the case in the young sporophyll of the living 



The Affinities of O. intermedium Hooker. 



Ophioglossum (Ophiodenna) intermedium Hook, is apparently 

 a very rare plant. It was originally described by Hooker from 



