115 
with a low central ridge and two slight parallel grooves on the 
ventral side; the filaments are capillary and nearly the length of 
the anthers ; the staminate scales are very early deciduous, falling 
away as the catkin elongates in growth; they are 5-6 mm. long 
and about the same width, with a cuneate base abruptly expanded 
above and lacerated, the lateral divisions ciliate; the line of 
junction of the lacerated portion with the basal part is of a darker | 
color than the base and quite conspicuous. 
The pistillate catkins are from 2 to 5 cm. long when the 
stigmas reach a receptive condition, and this appears to be the 
case just as the male flowers are mature. Their flowers consist. 
-of a single pistil in a calyx about 2 mm. high and half as wide, 
lacerate toothed at the summit and borne on a peduncle 2 mm. 
long (which elongates in fruit to 15-20 mm.) ; the pistil is about 
10 mm. high, its ovary obtusely triangular in section, with slightly 
concave sides and ovoid in shape, provided with three broad, 
parietal placentz, and containing many ovules; the style is 
slender and 2 mm. long; the stigma at first appears irregularly 
ridged, is 5 mm. across, and very fleshy, but not glutinous, and 
soon parts into three lobes, each of which is two or three-lobed, 
forming a quite complex structure. The pistillate scales are at- 
tached near the base of the peduncle, are 8-10 mm. long, con- 
cave around the flower, and provided with small lobes just 
above the stalk-like, flat base, and are ciliate all around, except 
the lower portion below these lobes. These scales are also 
fugacious, falling off with the slightest shock. 
A correction must be made in Dr. Watson’s ‘‘ Notes on 
American Poplars,’”’ in Amer. Journ. Sci., Vol. xv., 1878, where © 
P. heterophylla is grouped with P. tremuloides, Michx., and 
P. grandidentata, Michx., “styles two, with two or three nar- 
row or filiform lobes.’’ The style-lobes are dilated, and three in 
number. My specimens were obtained near Court House Sta- 
tion, Staten Island, where the tree is quite abundant on the bor- 
ders of swamps. I will gladly supply both kinds of flowers to 
those who care for them, and will collect mature fruit and leaves 
for distribution later in the season. 
os N. L. BRITTON, 
COLUMBIA COLLEGE, May 10, 1887. 
