SALICACEAE. — POPULUS 29 



acumen producta, toto circuitu glanduloso-crenata, glabra, ad 9 cm. 

 longa et 10 cm. lata; petioli 4-5 cm. longi, plus minusve comprcssi. 



15. P. nigra, var. italica. 



tt Folia subtus concoloria v. discoloria, supeme stomatibus haud praedita, 



turionum et ramorum plus minusve diversa, forma variabilia. Gemmae 



non viscosae, glabrae v. pubescentes Sect. 5. LEUCE. 



t Folia turionum subtus tomento albo persistente obtecta, margine lobata 

 V. irregulariter lobato-denticulata, ramorum fructiferorum sacpe gla- 

 brescentia et viridescentia, crasse papyracea. Gemmae plus minusve 



pubescentes Subsect. Albidae. 



Folia turionum plus minusve palmato-lobata, ramulorum fructiferorum 

 subtus vix glabrescentia, plus minusve cinerea, satis parva. 



16. P. alba. 

 Folia turionum irregulariter lobato-duplicato-dentata, ramulorum fruc- 

 tiferorum saepe valde glabrescentia, viridescentia, satis magna. 



17. P. tomentosa. 



tX Folia turionum subtus cinerea, pubescentia v. deinde glabrescentia, margine 



breviter denticulata, ramulorum fructiferorum sericea v. glabra, saepe 



glaucescentia, membranacea tenuiter papyracea. Gemmae saepis- 



sime glaibrae Subsect. Trepidae. 



Folia ramulorum fructiferorum distincte longe acuminata. 



18. P. adenopoda. 



Folia ramulorum fructiferorum obtusa, acuta v. breviter acuminata. 



Folia ramulorum fructiferorum late ovata v. ovato-rotunda, basi sae- 



pissime subito in petiolum brevem producta, saepissime glanduli- 



fera, apice breviter acuminata (v. acuta), margine satis anguste et 



regulariter gland uloso-serrulata (dentibus pro 1 cm. circiter 3). 



19. P.Sieboldii. 

 Folia ramulorum fructiferorum saepissime suborbicularia, basi rotun- 

 data v. pleraque truncata v. plus minusve cordata, rariter glan- 

 dulifera, apice obtusa v. acuta v. breviter acuminata, margine 

 sinuato-glanduloso-dentata v. eroso-crenulata, dentibus satis 

 remotis circiter 1-2 pro 1 cm. 

 Folia ramulorum fructiferorum basi nunquam cordata, rariter ro- 

 tunda, sed saepissime truncata, apice obtusa v. acuta. Amenta 

 fructifera vix plus quam 12 cm. longa ... 20. P. tremula. 

 Folia ramulorum fructiferorum basi saepe plus minusve cordata et 

 apice acuta v. breviter acuminata. Amenta saepe plus quam 12 

 cm. longa 21. P. rotundifolia. 



ENUMERATIO SECTIONUM SPECIERUMQUE ASIAE ORIENTALIS 

 NEC NON HIMALAYAE. 



Sect. 1. TURANGA Bunge in Mem. Sav. Str. Acad. Set. St. PHershonrg, VII. 

 498 (A. Lehmann. Rel. Bot. 322) (1851). — Gombocz in Math. Temiesz. Kdzl. XXX. 

 67 {Monog. Gen. Populi) (1908). 



Populus, subgen. Turanga Dode in Mem. Soc. Hist. Nat. Autun, XVIII. 

 (Extr. Monog. Ined. Populus 13) (1905). 



Folia polymorpha, utrinque cinereo-glauca et stomatibus numerosis praedita et 

 distincte reticulata, satis coriacea, basi glandulis vix v. haud prominentibus mu- 

 nita; petioli plus minusve rotundi. Gemmae haud v. paullo viscosae. Disci florum 



