592 



FILl CES. 



veloped fronds ; in both, stomata are confined to the recep- 

 tacle of the organs of reproduction. 



Ophioglossum has not gyrate vernation ; query, have the pri- 

 mordial fronds of any Ferns this gyration. The structure of the 

 fructiferous frond of Ophioglossum, would lead me to suppose 

 that this genus has only the first, or most simple primordial* 

 frond, and the fructiferous one ; if a barren one be found, it 

 will be at least once pinnate, Oph. pendulum has nothing to do 

 with general Ophioglossa. 



Connected with the above suspicions, are the questions, 

 what is the foliaceous part of the Fern, which is so in- 

 variably connected with Its reproductive organs. Common 

 parlance makes them to be fronds ; and such I take them 

 really to be, founding my opinion on their intimate associa- 

 tion with the reproductive organs, and the situation of these, 

 which in all genuine frondose plants, would appear to be in- 

 variably in collection with the lower stratum of tissue. 



It appears to be a curious fact, that while in genuine Atro- 

 genous frondose plants, the male organs always protrude 

 through the upper surface, the female generally, or always 

 takes a contrary direction, except when physical obstacles are 

 opposed to this. Their chief analogy with true leaves, consists 

 in their being the chief, parhaps sole organs of aeration. The 

 venation is more consonant with what we know to be the 

 mode of division in genuine frondose plants, than of true 

 leaves. 



If these foliaceous organs are frondose, and merely acces- 

 sory to reproduction, (in short analogous to the cap of Mar- 

 chantia) the ramenta must be the true leaves reduced to zero 

 as to function, agreeing intimately in structure with the 

 acknowledged leaves of Mosses and Jungermannia ; this may 

 be the reason of their universality. If these views are correct, 

 we have a beautiful instance of the male organs being a 

 simple modification of the leaves. 



If the ramenta are leaves. Ferns are allied to Lycopo- 

 diaccse j from which otherwise they are too much isolated. 



