182 Rhodora [OCTOBER 
origin here, and concludes that it is not indigenous, but must have 
been set out by some botánist. As, however, it still persists after 
twenty-two years left entirely to Nature’s care, and manifests no ten- 
dency to decrease in either numbers or vigor, I incline to the opinion 
of Mr. Higginson, that it originated here through natural agencies, 
probably from wind-sown spores, long antecedent to its discovery. 
The plants grow in the crevices on one rock, which is only six feet 
through at the base, and five feet high. The fronds do not possess 
the luxuriant growth exhibited in its natural habitat, the largest fronds 
being nine to ten inches long, and five-eighths inch wide at base, with 
little disposition to produce auricles, or to root at the tips. 
Lygodium palmatum, Swartz. This rare fern grows in Dover, ad- 
joining Needham, where I have collected beautiful, fully fruited 
specimens. It occupies a small space in a shrubby pasture, the fronds 
climbing principally on Spiraea salicifoiia. 
FLORA OF THE POCONO PLATEAU. 
Thomas C. PORTER. 
RHODORA is certainly a well-chosen name for the journal of the 
New England Botanical Club, both because of its euphony and be- 
cause borrowed from a genus of plants represented by a solitary 
species, and that a hardy shrub which produces unique and beautiful 
flowers. And yet, this shrub, immortalized by Emerson in verse, is 
not, as some might suppose, confined to New England, for it exists 
elsewhere, in Canada and northern New York, and has, besides, a range 
much farther south. On the Pocono Plateau, embracing the western 
half of Monroe County, Pennsylvania, and portions of the adjioning 
counties, it flourishes in many places and when in full bloom, early in 
June, along with the Azalea canescens of Michaux, fills the swamps 
and open woods with a glorious display. The latter sometimes attains 
the height of ten feet and is readily distinguished from the allied 4. 
nudiflera by its hoary leaves and the single set of short gland-tipped 
hairs on the tube of the corolla. 
'The Pocono region, as well as the mountains to the north, south and 
west of it, has an elevation of from 2000 to 2300 feet above the sea, 
and hence its mean annual temperature is nearly that of the Adiron- 
dacks and Mount Desert Island. Lying, too, within the great bowlder- 
line, it has been the theatre of immense glacial action, the results of 
