MR MACVICAR on the Germination of the Filices. 265 



greatest fault in his observations is, that he neglected to observe 

 a most interesting process in the evolution, and by proceeding 

 per saltum from the period at which a high magnifier was ne- 

 cessary to render his early forms visible, to the time when 

 these appeared to the eye as small scales, he has represented 

 forms nowise connected with each other, which has led late 

 observers to doubt their accuracy. Of these, the most distin- 

 guished is the author of the article Filices in the Edinburgh 

 Encyclopaedia, published in 1815. The experiments which he 

 there describes commence soon after what he terms the " seed- 

 lobes" become visible to the naked eye. Of course they corres- 

 pond to the second sets of LINDSAY'S observations, and, though 

 much more perfect, are on a general view pretty similar. He 

 has remarked the temporary radicles, the true root, and the 

 elevation around the opening formed by the emission of the 

 true frond, on all of which LINDSAY is silent. Besides these, 

 several others have noticed ferns in the act of germinating. 

 EHRHART seems to have observed some of the earlier forms of 

 LINDSAY. SPRENGEL saw a single species in a state of sponta- 

 neous germination, in its farthest advanced states, forms in which 

 young ferns are to be seen in every shady moist crevice, or other 

 place where ferns grow. MIRBEL has also observed some of the 

 later stages, differing in some unimportant particulars, in the 

 form of what have been named the Seed-lobes. 



Notwithstanding, however, that observers have been so nu- 

 merous, it does not appear that the true mode of the evolution 

 has as yet been understood. LINDSAY makes no attempt to re- 

 concile his -early with his later forms ; while the author of the ar- 

 ticle Filices, though he made experiments on various genera, 

 could never observe the first forms of LINDSAY. These circum- 

 stances are easily explained, however, if the appearances present- 

 ed during the evolution of Poly podium vulgare be similar to 



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