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Ghiwa: N. 1988, in cultivated land. July 15. 1899. 

 Area: Europe, western and middle Asia, East-India, Sibiria. 



2. P. balsamifera L. ; Hook. ft. brit. Ind. V p. 638; 0. Fedt- 

 schenko Spisok rast. p. 142. 



var. laurifolia (Ldb.) Wesm. DC Prod. XVI p. 330 ; Franchet 



pi. turk. 1. c. p. 253 ; 0. Fedtschenko I.e.; — P. laurifolia Ldb. fl. 

 alt. IV p. 297; Ldb. fl. ros. III p. 629; Ldb. le. pi. fl. Ros. t. 479. 



Pamir: N. 1339, prov. Wakhan, in cultivated land at Langarkisht. 

 Alt. 3000 m . Sept. 10. 1898. 



Area: Northern America, Europe, Sibiria, Asia-Media. 



3. P. pyramidalis Roz.; Bois. fl. or. IV p. 1194. 

 Samarkand: N. 85, cultivated. May 3. 1898. 

 Area: Europe, western Asia. 



4. P. pruinosa Schrenk; Ldb. fl. ros. Ill, p. 628; Trautv. Enum. 

 Song. 1. c: p. 91; Rgl. et Herd. pl. Semenov. 1. c. p. 97; Rgl. Acta 

 H. Petrop. VI p. 474; 0. Fedtschenko Spisok rast. p. 142; Herb. fl. Ros. 

 N. 1135, 1135 a et b. 



Regel (Acta H. Petrop. VI) consider P. pruinosa as a variety of the 

 following species, but he is not right in doing so. Hitherto P. pruinosa 

 has been imperfectly described, neither of the descriptions mentioning the 

 catkins. Now, in the „Schedae ad Herbarium florae Rossicae", Mr. Lit- 

 winow gives the following remarks on the difference between this species 

 and P. euphratica : ,A P. euphratica differt praeter indumentum gemma- 

 rum ramulorumque juniorum et foliorum formam (quae in P. pruinosa 

 minus variabiles sunt), perigonio ad medium v. ad basin usque in dentes 

 crebriores diviso, non margine tantum dentato , stigmatibus laxioribus 

 (longius pedicel latis), antheris obtuse apiculatis, nec omnino muticis." 



Besides, the catkins of P. pruinosa often are shorter and more dense- 

 flowered and the capsules are velutine. And having seen a series of 

 samples of both species I can add , that the variation of the leaves in 

 the two species is quite different, P. pruinosa varying from reniform and 

 subvelutine to ovoid and densely velutine, and the glabrous P. euphratica 

 from reniform through ovoid to linear. See the figures. 



Transcaspia: N. 192, cultivated at Tshardshui. May 5 1898; 

 — Amu Daria: N. 1824, on an Island („Shatman Togai") between 

 Tshardshui and Chiwa. June 19. 1899. A tree 8 ra high ; N. 1825, Ibid. 

 A shrub, 1 — 2 m high. Leaves oblong-ovoid, white velutine; N. 1860, 

 Kavak-lé at the river Amu Daria, between Tshardshui and Ghiwa, in 

 forests. June 23. 1899. 



Area: Middle and central Asia. 



