20 WILSON EXPEDITION TO CHINA 
Fischer founded this species, as Henry has already pointed out (l. c.) on the type 
of Pallas’s figure, of which Fischer had the original specimen in his collection. Later 
authors, like Maximowicz and Komarov (see under P. Mazimowiczii) took the 
eastern plant for the type (at least partly); this has been separated with good reason 
by Henry as a different species, P. Mazimowiczii. The type is also represented for 
the first time as P. foliis ovatis acutis Serratis by Gmelin's plate (Fl. Sibir. 152, 
t. 33 [1747]). To this typical P. suaveolens may belong Maximowicz’s P. suaveo- 
lens, var. a (in Bull. Soc. Nat. Mosc. LIV. 51 [1879]), at least concerning the speci- 
mens of Tatarinow and Bretschneider if they do not belong to P. Simonii. The 
Kansu specimen of Piasezki I refer to var. Przewalskii (see p. 32). It is often very 
difficult to determine herbarium specimens and to keep apart the forms of P. 
suaveolens, P. Maximowiczüi, P. Si ii and P. laurifolia. Turczaninow (in Bull. 
Soc. Nat. Mosc. XXVII. 398 (1854); Fl. Baical'-Dahur. II. 124 [1856]) describes 
the variability of the leaves of P. suaveolens, mentioning three different forms. 
Gombocz does not separate S. Mazimowiczii from P. suaveolens. 
In western Szech'uan from 1000-3300 m. altitude, this is very common on the ~ 
banks of rivers and in the forest and has been very extensively planted as a shade 
tree in the warm semi-arid valleys. It is a favorite with Tibetan monks, and their . 
lamasaries and dwellings are generally shaded by groves of this Poplar. It is a 
large tree, often 30 m. tall, with massive wide-spreading branches. The trunk i8. 
thick and the bark is smooth and pale gray on young trees but becomes dark and 
fissured with age. The leaves vary in size considerably and the branchlets are 
always glabrous. Pictures of this tree will be found under Nos. 223 and 0334 of | 
the collection of my photographs and also in my Vegetation of Western China, No. 
396. BE HL Ww. 
Populus szechuanica Schneider, n. sp. 
Arbor ad 40 m. alta, trunco circuitu ad 4 m.; ramuli juveniles | 
(turiones) distincte angulati, olivacei v. purpurascentes, glabri, vetus- - 
tiores teretes, flavo-brunnei, deinde cinerascentes; gemmae purpuras- | 
centes, glabrae, viscosae, acutissimae. Folia initio rubescentia, pa- - 
pyracea, supra intense viridia, glabra v. basim versus puberula, subtus 
albescentia, non v. vix puberula, nervis primariis et ex parte secundariis © 
distinctis, turionum saepissime ovato-elongata, basi leviter v. distincte 
cordata v. rotunda, apicem versus sensim acuta v. breviter acuminata, | 
margine anguste glanduloso-crenato-dentata, 11-20 cm. longa et 5-11 
em. lata v. usque ad 28 cm. longa et ad 16 em. lata, ramulorum fructi- 
ferorum late ovata v. ovato-rotunda, basi rotunda v. plus minusve 
cordata; minima ovato-lanceolata basi leviter acuta, apice saepissime 
subito breviter acuminata, margine plus minusve distincte glanduloso- 
dentata, initio ciliolata, 8-18 em. longa et 5-15 cm. lata; petioli folio- 
rum turionalium satis breves, 2-4 em. longi, foliorum ramulorum satis 
elongati, 2.5-7 cm. longi, semper glabri. Amenta tantum fructifera | 
vidi, ad 16 em. longa, glabra; capsulae subsessiles, glabrae, 3-4-valvae, 
ut videtur, ovato-globosae, 7-9 cm. longae, basi perianthio glabro 
irregulariter lobato cinctae. 
