30 WILSON EXPEDITION TO CHINA 
decidui, distincte lobati; stigmata 3, stylosa; stamina, circiter 12, antheris longis, y 
apice apiculatis. Capsulae elongatae, pedicellatae. 
1. Populus euphratica Olivier, Voy. Emp. Othoman. III. fig. 45-46 (1807). — 
Wesmael in Mém. Soc. Sci. Hainaut, 111. (Monog. Populus, 54, t. 10-13) (1869). — : : 
Brandis, Forest Fl. Brit. Ind. 474, t. 63 (1874). — Hooker f., Fl. Brit. Ind. V. 6388 — 
(1888). — Burkill in Jour. Linn. Soc. XXVI. 536 (1839). — Dode in Mém. Soc. 
Hist. Nat. Autun, XVIII. (Extr. Monog. Inéd. Populus, 16, t. 11, fig. 1, 19, 1°, 1°) 
(1905). — Gomboez in Math. Termesz. Kózl. XXX. 68 (Monog. Gen. Populi) (1908). 
Populus diversifolia Schrenk in Bull. Acad. Sci. St. Pétersbourg, X. 253 (1842); 
in Fischer & Meyer, Enum. Alt. Pl. Nov. Schrenk. 15 (1842). — Trautvetter, 
Pl. Imag. Fl. Russ. 23, t. 16 (1844). — Dode in Mém. Soc. Hist. Nat. Autun, 
XVIII. (Extr. Monog. Inéd. Populus, 15) (1905). 
Balsamiflua deltoides Griffith, Icon. Pl. Asiat. IV. t. 526 (1854). 
Populus Ariana Dode in Mém. Soc. Hist. Nat. Autun, XVIII. (Eztr. Monog. 
Inéd. Populus, 16) (1905). 
Populus Litwinowiana Dode, l. c. 17 (1905). 
CHINA. Chili, Peking, R. Alcock (fide Burkill); Kanou, beyond the Great 
Wall, P. J. Piasezkei (fide Maximowiez). Also in northern Africa and western 
and central Asia. 
I doubt, however, if Alcock's specimen from Peking belongs to this species. 
2. Populus pruinosa Schrenk in Bull. Acad. Sci. St. Pétersbourg, III. 210 (1845). 
Wesmael in Mém. Soc. Sci. Hainaut, III. (Monog. Populus, 56, t. 14) (1869). — 
Dode in Mém. Soc. Hist. Nat. Autun, XVIII. (Extr. Monog. Inéd. Populus, 18, 
t. 11, fig. 22) (1905). — Gombocz in Math. Termesz. Közl. XXX. 72 (Monog. Gen. 
Populi) (1908). 
Populus glaucicomans Dode in Mém. Soc. Hist. Nat. Autun, XVIII. (Extr. 
Monog. Inéd. Populus, 18, t. 11, fig. 2) (1905). 
TURKESTAN, SOUTHWESTERN SIBERIA. 
According to the photographs and notes taken by the well-known explorer F. N. 
Meyer on February 19, 1911 in Chinese Turkestan for the Department of Agricul- 
ture of the United States, P. pruinosa may be distinguished from P. euphratica 
by the bark of old trunks. Meyer's photograph No. 5685 shows a trunk of P. 
pruinosa with a distinctly and deeply grooved bark as in Ash and Elm trees, while 
the photograph No. 5689 represents P. euphratica with a more or less shaggy bark. 
Sect. 2. LEUCOIDES Spach, Hist. Vég. X. 385 (1841). — Gombocz in Math. 
Termesz. Közl. XXX. 118 (Monog. Gen. Populi) (1908). 
Populus, subgen. Eupopulus Dode, sect. Leucoideae Dode in Mém. Soc. Hist. — 
Nat. Autun, XVIII. (Extr. Monog. Inéd. Populus, 14 et 35) (1905). 
Folia ramulorum turionumque vix diversa subtus plus minusve discoloria, basi — 
glandulifera, superne stomatibus non praedita; petioli basi cylindrica, apice p 
compressi, semper satis longi. Gemmae vix viscosae. Disci florum persistentes, 
satis evoluti, fere ad basim lobati; stigmata 2-3, stylis elongatis; stamina 30-40, 
antheris longis, apice apiculatis. Capsulae crassae, pedicellatae (an semper?), 
3. Populus Wilsonii C. Schneider. See p. 16. 
4. Populus glauca Haines in Jour. Linn. Soc. XXXVII. 408, fig. (1906). — Gom- _ 
bocz in Math. Termesz. Közl. XXX. 157 (Monog. Gen. Populi) (1908). 
