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lower part dark, upper part stramineous ; rachis 6 centi- 

 meters long up to the point where it forks, lamina 5 cen- 

 timeters wide at base where it is broadest, fully pinnate, 

 the pinnae rapidly decreasing in length from the middle 

 upward, the 2 centimeters at tip divided and beautifully 

 crested, the rest more or less dentate ; seven lower pairs 

 fully separate from each other, the lowest 1 centimeter 

 from the pair above, the four lower pairs rounded at base 

 and stalked, those above more and more adnate and de- 

 current; texture moderately thick, but veins distinct, 

 being more or less sunk in the parenchyma, nearly all 

 but the one or two lowest on such pinnae being simple, the 

 lowest once or twice forked each vein running into a 

 crenature, the outermost flabellate. Fruit not known. 

 There are some peculiar features belonging to this fern. 

 The most remarkable one for a variety of P. vulgar e is 

 that the four or five lowest pairs of pinnae are stalked 

 with a pedicel. No other form of the species with which 

 I am acquainted possesses this feature. Without excep- 

 tion all the other forms have adnate pinnae throughout, 

 except that anomaly in the species called corymbiense, 

 and even that has the green part a trifle expanded at the 

 base of the pinnae. Some forms of var. cambriciim come 

 near to it in this respect, such as cambriciim itself and 

 the variety Prestonae, which is found only in the lake dis- 

 trict of England. In the lower pinnae of these the paren- 

 chyma is entirely eliminated from the under side of the 

 veins at the base of the pinnae, and is very much narrowed 

 on the upper side, so that the pinnae are fully separated 

 from those above. Still, they are not stalked. 



Another peculiar feature is the simple unbranched 

 veins which extend quite to the edge of the pinnae. This 

 also is an anomaly in the species. The dark shade of the 

 lower part of the stipe and of the upper part of the rachis 

 is another peculiarity. In the fresh plant the costae of the 

 stalked pinnae and the rachis above the point where it 

 forks are as dark as in the ebony spleenwort. But when 

 pressed the greater part of this discoloration disappears. 



