12 Rhodora [JANUARY 
2-4 dm. high, with habit somewhat as in Sisymbrium altissimum; 
stem retrorsely pubescent, the hairs being simple; leaves oblong 
in general outline, deeply pinnatifid to decidedly bipinnatifid, the 
lobes rounded, the sinuses broad and usually obtuse or truncate; 
racemes at length elongated, loose, the pedicels slender, ascending or 
so widely spreading as to be nearly horizontal, in fruit 6-10 mm. long, 
the lower ones subtended by distinct (though much reduced) leaves 
or leaflike bracts; flowers of medium size; petals pale yellow, 5 mm. 
in length; pods linear, subterete, 2.5-3.5 cm. long, 1-2 mm. in thick- 
ness, tipped with a slender style about 3 mm. long; seeds essentially 
in a single row in each cell.— Widely distributed in Central and West- 
ern Europe; adventive along railways, Milwaukee, Wisconsin, Wm. 
Finger, and Sherborn, Massachusetts, Miss M. L. Loomis. 
Little difficulty should be experienced in recognizing this species, 
for its characteristic bracts, though not specially conspicuous, are 
readily seen and form a feature unusual in cruciferous plants. 
GRAY HERBARIUM. 
POPULUS VIRGINIANA AND P. ANGULATA. 
H. H. BARTLETT. 
In American botanical works it is customary to include in the 
synonymy of Populus deltoides several names which are maintained 
in Europe for trees of marked specific characters. Thus, Schneider ' 
distinguishes three species, Populus deltoides, P. monilifera and P. 
angulata in place of the P. deltoides of our manuals. In his Elysium 
Marianum, Mr. Tidestrom ? maintains the first and second of these 
three as distinct (under the names Aigeiros deltoides and A. virginiana) 
but the third is not recognized in any current American work. Last 
October the writer found Populus virginiana and P. angulata growing 
abundantly on both the South Carolina and Georgia sides of the Sa- 
vannah River, at Augusta. They were so clearly different species that 
specimens were collected for identification by Mr. Tidestrom, who is 
now studying the poplars. 
! Tllustriertes Handbuch der Laubholzkunde, i, pp. 7-9 (1904). 
? Elysium Marianum, iii, part 13, pp. 16-17 (1910). 
