CANADIAN FILICINEA 207 



young) with pale brown scales ; fronds bright green, erect, narrowly oblong-ovate, usually 

 12 to 15 inches long by 4 to 7 inches wide, smooth, and bipinnate ; pinna; short-stalked, 

 oblique to the rachis, elongated triangular, the lowest pair broadly triangular with the 

 inferior pinnules twice, or nearly twice, as long as the superior, the basal ones longest of 

 all; pinnules also obliquely set, connected by a very narrow wing, oblong, sub-acute, 

 incised or pinnatifid ; lobes spinulosely toothed, especially at the apex ; indusia smooth, 

 and without marginal glands. 



Innumerable varieties and forms of this plant have been recorded and described, all 

 of which, however, are either monstrosities or can, without much straining, be referred 

 either to the typical form or the vars. intermedium and dilatation. 



Var. intermedium, D. C. Eaton, (A. intermedium, Willd., A. Amerkanum, Davenport, Lastrea 

 intermedia, Presl.), has the scales few and tawny ; fronds dark green, oblong-ovate, broader 

 and often larger than in the typical plant, twice or often thrice pinnate, under surface mi- 

 nutely glandular; pinna 1 spreading, oblong-lanceolate, the lowest pair somewhat trian- 

 gular with the inferior pinnules moderately elongated, but the basal ones a little shorter 

 than the next ; pinnules also spreading, ovate-oblong, acntish, pinnatifid or pinnate ; 

 ultimate segments oblong-ovate, obtuse, and spinulosely toothed on both sides and apex ; 

 margin and often the surface of the indusia covered with stalked glands. 



Var. dilatalum, Horneman, (A. dilatalum, Swz., Lastrea dilatata, Presl , Nephrodinm dila- 

 tatum, Desv.), has the scales large and brown, often with a darker centre ; fronds very dark 

 green, broadly ovate or triangular-ovate, usually much exceeding, especially in breadth, 

 the other forms, thrice pinnate; pinna' spreading, broadly triangular with the inferior 

 pinnules much longer than the superior, the basal ones on the lower side longer than the 

 next but on the upper side usually shorter than those next them ; pinnules lance-oblong 

 and deeply pinnatifid ; ultimate segments oblong and toothed ; indusia smooth. A dwarf 

 state of this variety is var. dumetorum, which fruits freely when 5 to 8 inches high, and 

 has compact bipinnate fronds, with the inferior basal pinnules but little elongated. 



Numerous other sub-varieties of A. spimdosum have been noted, including var. obliquum, 

 which is a rather rigid, more than usually chaffy form of the typical plant, with pinnae 

 and pinnules obliquely set, and var. recurvalum, which shows a recurved convex growth 

 of the frond, pinnae and pinnules. A British Columbian plant from Vancouver Island is 

 much laxer than common, and has the pinna 1 , pinnules and segments more distant, taper- 

 ing and acuminate ; the pinnules, too, are narrower throughout, and the whole fern is 

 more rigid than is usually seen. Occasionally specimens are found with glands scattered 

 over the upper as well as the under surface of the fronds, and bifurcating and crested 

 forms occur both in the species proper and in its varieties. 



Under its A r arious forms this species crosses the continent, and is known to range 

 northward to Alaska and beyond the Peace and Churchill Pavers. Occurring in the 

 wooded districts of all the Provinces, in some places, notably the Island of Antieosti, 

 Eastern Quebec, and to the west of Lake Superior, it forms almost the whole undergrowth. 

 The typical plant is probably the least common form with us, but has been seen in Nova 

 Scotia, New Brunswick, Quebec, Ontario, arid, according to Prof. Eaton, about Lake Su- 

 perior and westward to British Columbia, Vars. intermedium and dilatalum also extend 

 from the Atlantic through the Rocky Mountains to the Pacific, but while the former, 

 which loves drier woods than the normal form, is par excellence the usual form in Eastern 



