1910] Fernald and Wiegand,— Botanizing in Maine 145 
in the yard of the Grand Trunk Railway at Portland, Maine, and by a 
roadside in Pembroke, Maine. 
ARNICA MOLLIS Hook., var. PETIOLARIS Fernald. A small colony 
of this plant was found in a marly, springy spot at the foot of a steep 
bank below the Falls of the Aroostook River about one mile above 
Four Falls, New Brunswick. ‘This is the first station recorded east 
of Moxie Falls, Somerset County, Maine. 
LaPsANA COMMUNIS L. This plant was found in considerable 
abundance along the pavement on one of the streets of Rockland. It 
has previously been found on Mt. Desert Island and perhaps else- 
where, but is a rare plant in Maine. 
SONCHUS ARVENSIS L., var. GUABRESCENS Wimmer & Grabowski, 
Fl. Sil. pt. 2, ii. 220 (1829). In the typical form of the species the 
peduncles and involucre are more or less densely glandular-hirsute. 
This form is the ordinary one found throughout the range of the 
species in America. However, a colony was found along the strand 
on Carlow Island, Passamaquoddy Bay, the involucres and pedicels 
of which were entirely glabrous. This evidently is the form recognized 
in Europe as var. glabrescens W. & G. In addition to these plants 
we have seen specimens of this variety from Marne: Limestone, 
September 10, 1896, Fernald; Dover, September 1, 1894, Fernald. 
MassacHUSETTS: Lenox, August 24, 1902, R. Hoffmann. Onto: 
near Soldiers Home, Erie County, August, 1902, W. P. Holt. It 
seems, therefore, to have a fairly wide distribution. 
LACTUCA CANADENSIS L., and L. HigsuTA Muhl. Although no 
specimens of L. hirsuta were collected, the occurrence of occasional 
plants of L. canadensis with the petioles and midribs of the basal leaves 
hirsute makes it desirable to distinguish these two species, if possible, 
by some other characters. A study of the material in the Gray 
Herbarium and the Herbarium of the New England Botanical Club 
shows that good characters may be drawn from the achenes, and that 
there are also some other minor differences. The leaves, though 
variable as in most species of Lactuca, nevertheless show some ten- 
dencies which are helpful. The two species differ as follows:— 
L. HIRSUTA. Lateral leaf-divisions oblong-obovate, commonly 
broadest above the base, often more or less truncate, usually 
dentate: involucre, when fully developed, 16-22 mm. long: 
mature achenes 7-9 mm. long from base to tip of beak: pappus 
9-12 mm. long. 
L. CANADENSIS. Lateral leaf-divisions rarely oblong or obo- 
