550 
one double plant from Brattleboro, Vermont, with two large nor- 
mal fronds, and Austin collected similar specimens at Closter, New 
Jersey. Prof. Macoun, however, found two and three fronds to- 
gether on grassy banks at Hastings, which are quite unlike 0. 
vulgatum, and yet are larger than O. arenarium. 
All these variations suggested an inquiry as to what might be 
considered typical O. vaigatum. The description in Gray’s man- 
ual reads: “ Sterile frond (in the N. American form) obovate or 
ovate with a tapering sessile base and mostly borne below the 
middle of the stalk of the fertile spike.” The figures given in the 
Manual show a large ovate-lanceolate sterile frond, 6 cm. long by 
3 cm. wide. Very few American specimens have been seen 
which agreed with this figure, but they have been collected by 
Alvah A. Eaton in New Hampshire, Alfred Commons in Dela- 
ware, McCulloch in New Brunswick and Austin in New Jersey. 
The commonest form throughout the Northern and Eastern states, 
however, is like the figure given by Prof. Eaton in his Ferns of 
North America, which he describes as “sterile segment fleshy, 
sessile near the middle of the plant, ovate or elliptical, one to three 
inches long.” His figure shows an oblanceolate frond, blunt at 
apex and tapering to a long narrow base. Elliptical fronds also 
are common, and the figure given in the Linnaean Fern Bulletin 
for October, 1896, fairly represents a common American variation. 
None of the oblanceolate fronds have been seen from Europe, 
though shorter and broader oval fronds occur on both continents, 
as well as the longer elliptical ones; a broad; blunt and distinctly 
ovate form is also common to both. Linnaeus describes the frond 
as ovate and cites Plumier’s figures, which, unfortunately, I have 
not been able to see. The common European form, however, 
seems to be more acute and ovate-lanceolate, with an amplexicaul 
base, and is, therefore, often carinate; in American specimens it 
is very rare to find a leaf that is keeled owing to the tapering flat 
base. Specimens seen from England, France, Germany, Hungary 
and Switzerland are all broadest just above the base, and taper to 
an acute apex, 
The venation varies according to the size and shape of the 
frond; in the ovate and oval forms the short marginal areolae, 2 
each with a single short, free veinlet, are more numerous; in the 
