1911] Bartlett,— Gynodioecism in Plantago lanceolata 199 
“Cosi il Pioppo nero della Virginia (Spec. I. var. 8) sembrami una 
varieta del Pioppo nero d’ Europa, benché il Sig. Fougeroux de Bondaroy 
nelle Memorie della Societá d'Agricoltura, che si stampano a Parigi, 
ne formi una nuova specie. Quest’ albero s'innalza a settanta, ed 
ottanta piedi formando una cima rotonda, le sue foglie sono sostenute 
da lunghi picciuoli spesso tinti di rosso, e sono quasi a figura di cuore, 
scannellate al margine, e liscie da ambe le parti... .” 
Leaves of an ovate type. 
POPULUS DELTOIDES Bartr., Marsh. 1. c.? 
P. canadensis Moench, Weisenst. 81, 1785; Asch. & Graebn. 
Syn. 4: 33, 1908. 
? P. marilandica Bosc; Poir. in Lam. Enc. Suppl. 4: 375, 
1816. 
Aigeiros deltoides Tm. l. c. 
Similar in stature and form to the preceding: branchlets smooth, 
yellowish-brown: buds dark olive-brown, pointed; normal leaves 
8-10 em. in length, deltoid-ovate, base rounded; crenate-serrate to 
within 1 em. of the apex; leaves of the root-shoots and uppermost 
branchlets 15 cm., more or less, in length, and as wide, base truncate: 
staminate aments about 1 dm. in length; stamens about 40, anthers 
dark red. 
It is to be hoped that local botanists will take up the study of their 
native poplars so that we may know at least as much about our trees 
as is known in Europe. Concepts based on herbarium specimens 
alone often tend more to confuse than illuminate. 
Bureau or Puant Inpustry, Washington, D. C. 
ON GYNODIOECISM IN PLANTAGO LANCEOLATA. 
HARLEY Harris BARTLETT. 
In 1879 Franz Ludwig! published an account of the forms of the 
flower in Plantago lanceolata, in connection with a general discussion 
1 F. Ludwig: Ueber die Blütenformen von Plantago lanceolata L. und die Erschein- 
ung der Gynodiócie. Zeitschr. fiir die gesammten Naturwissenschaften, lii (1879), 
p. 441. Review in Bot. Centralb. i (1880), p. 331. 
