126 
BEAUTIFUL FERNS. 
icate than the frond itself. The sporangia are comparatively 
scanty, and are fully covered by the involucre. The spores 
are spheroid-tetrahedral and obscurely trivittate. 
Mr. Moore and some other authors are disposed to in- 
sist on the right of priority belonging to the specific name 
Stelleri. But the name gracilis has been used by nearly 
every writer on American Ferns since the time of Michaux, 
and will most probably be kept up rather than the other. 
It should be noted that Ruprecht considered his Alloso- 
rus Stelleri to be distinct from our plant, and mentions 
several points of difference in his work on the Distribution 
of Vascular Cryptogamia in the Russian Empire. 
The figure is taken from specimens collected in Sunderland, Hamp- 
shire County, Massachusetts, by the late Rev. David Peck. 
