2U JOURNAL OF THE ARNOLD ARBORETUM [vol. i 



ENUMERATIO SPECIERUM 



1. S. Richardsonii Hooker, Fl. Bor.-Am. ii. 147, 1. 182 (1839).— Andersson 

 inDe Candolle, Prodr. xvi.- 273 (1868), incl. var. lailJoUa et angxiKt'iJoUa. — 

 Seeniann, Bot. Voy. Herald, 40 (Fl. West-Eskim.-Land) (1852 .57). — 

 Bebb in Bot. Gaz. xvi. 50 (1889), ex parte. — Coville in Proc. Wash. Aead. 

 Sei. II. 315, fig. 19 (1901). — Osteiifcid in Vid.-Sel.sk. Skrift. I. Matli.-Nat. 

 KI. 1909, no. 8, 35 (Vase. PI. Aret. N. Am. Gjiia Exp.) (1910). — S. 

 {lanata) amcricana b. lUchardsoni Andersson in Ofv. Svensk. Vet.-Akad. 

 Forh. XV. 119 (1858); in Walpers, Ann. Bot. v. 747 (858). — S. lanata, var. 

 americana forma jS. *,S. Richardsoni Andersson in Proc. Am. Acad. vi. 59 

 (Sal. Bor.-Am. 13) (1858). — S. lanata amcricana Andersson in De Candolle, 

 Prodr. XVI.- ^274 (18G8), pro synon. — In 1889, BeM>, and in 1901 (^oville 

 already dealt with this interesting Arctic species the type of which was col- 

 lected by Dr. Richardson at Fort Franklin on the Mackenzie River. I 

 have seen a i)hotograi)h and fragmenls of the female ty])e preserved in Herb. 

 Kew. Hooker did not know the male plant, but Richardson also collected 

 specimens with staminate aments as Bebb has already pointed out. Bcbb, 

 howcVer, referred to S. Richardsonii a specimen from Labrador which be- 

 longs to S. calcicola. 



The leaves of S. Richardsonii are not entire as Hooker stated. On his 

 own plate he clearly shows a denticulate base of a leaf. Sometimes the 

 leaves are even rather distinctly denticulate as in Eastwood's no. 385 and 



in Chapman's 41a. 



The geograijhical distribution of this species is clearly indicated by the 

 specimens enumerated l)elow. There are two specimens which I am not 

 able to identify correctly. One was collected Ijy J. Macoun on Hunker 

 Creek in the Yukon Territory, July 24, 1902 (No. 5439G, ().; fr. im.; G., 



N., W.). It had been named S. Lyallii (Sarg.) Heller?, and by Rydberg 

 S. Barchn/i. The fruiting aments are quite like those of S. Ricluirdsoniihnl 

 the pedicels are as long as the gland. The young twigs are rather yellowish 

 and partly glabrescent, and the older branchlets are more like those of S. 

 Richardsonii with a looser ])ubescence. The leaves and stipules do not differ 

 from those of this species, and it may be only a form of it, or a hybrid from 

 it. The second doubtful specimen was brought by F. Johansen from Ber- 

 nard Harbour, August 7, 1915 (No. 308 b -= 93781, 0.; f., fr.; " a bush "). 

 On this specimen the ovaries are partly sparsely pilose but the fruits are 

 glabrous. I presume that S. Richardsonii also has a form with nK)re or less 

 hairy ovaries as this occurs in certain groups in almost every sj)ecies with 



glabrous pistils. 



Andersson, in 18G8, described two forms; lafifolia and angustifolia. I do 



not think that they arc of any taxonomic value because both forms of 

 leaves are to be found on the same j)lant. 



As Ostenfeld has already pointed out, the most prominent characters of 

 this Willow are; " the stout hairy young twigs, the large ])erslstent glandu- 

 lar-serrate stipules, and the smooth leaves with at the base sparingly glan- 



