Bower. — Studies in the Phytogeny of the Filicales. 365 
made, was in danger of passing entirely out of view. For instance, Diels 
places the Woodsieae-Onocleinae quite apart from the Asplenieae- 
Blechninae, and does not indicate their relationship in the text (Engler 
u. Prantl, i. 4, pp. 164 and 245). Christ also separates Onoclea and 
Struthiopteris (Farnkrauter, p. 284) widely from Blechnum (p. 176), as 
though there were no near kinship between them. It will be another object 
of this inquiry to see whether there is not ground for bringing again into 
notice a relationship which has thus been allowed to drop. 
On the other hand, there are the closely related genera of Woodwardia, 
Doodia , and Sadleria. The synonymy of these genera indicates their near 
alliance with one another, while in all the leading systems they have been 
placed in juxtaposition with Blechnum.. The justification for this must be 
examined, with a view to their possible phyletic seriation. 
Again, Stenochlaena , which has been referred to Lomarijx by Willdenow, 
to Onoclea by Swartz, and to Acrostichum by Baker, will require careful 
examination, to test the position now assigned to it with the Ferns above 
named. Brainea also, though a more isolated genus, will have to be com- 
pared, as it has been referred to this affinity by certain writers. 
It will be necessary to submit these Ferns to anatomical and develop- 
mental study. The vascular system of many of them is very imperfectly 
known, and in some has never been adequately examined. But the most 
important point of all for this inquiry will be the characters of their sori. 
The differences in the relation of the sori to the apparent leaf-margin in the 
various species now included in Blechnum have never been submitted to 
adequate developmental examination. Nor has any developmental com- 
parison been made of them with the divergent genera Woodzvardia, Doodia , 
and Sadleria , nor yet with Stenochlaena. The only comparative observa- 
tions bearing on the development, and they are very imperfect and restricted 
in their scope, are those of Burck (Indusium der Varens, Haarlem, 1874). 
Mettenius, however, made valuable comparative observations on the more 
mature state of the sorus in numerous species (Fil. Hort. Lips., p. 60). 
Nevertheless, the field may be held to be here still open for more detailed 
comparative study of the sori than has yet been made. It would be 
desirable, no doubt, to extend the observations to other criteria than those 
named. This must, however, stand over for the present ; and something, at 
all events, will be gained which may lead to more confirmed opinions than 
are at present possible, if the relationships above indicated are tested more 
fully through the characters of anatomy and the development of the sorus. 
But there is yet another relationship that will have to be considered, 
since it has been very definitely indicated by systematists. It is the relation 
of the Ferns named to the Asplenieae. This, however, is an ulterior 
question. Before it can be adequately discussed it will be necessary to 
have some clearer knowledge of the probable phyletic relationships of the 
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