102 JOURNAL OF THE ARNOLD ARBORETUM [vol. ii 



which seems to be a widely spread species of which I have seen specimens 

 from Alberta, Saskatchewan, Idaho, Montana, North and South Dakota 

 (det, by Ball), Wyoming, Oregon, Utali, Colorado, Nevada and California. 

 Here we find the so called S. cordata var. Watsonii which occurs according 

 to Jepson on the San Jacinto Mts. and the northern Sierra Nevada. 



The type of Andersson^s S. cordata angudata viielUna had been collected 

 by Bourgcau in Saskatchewan 'M)ords de la riviere i cotd des Bergcs Carl- 

 ton," I have seen co-types of it in Herb. Berol. but I am not acquainted 

 with Andcrsson's form S. cordata 2. S. angusiata vitellina crassa^ mentioned 

 only in 18G7, based on another specimen of Bourgeau's from "dans le 

 marais glace pr5s le Fort Carlton." 



1 supi)ose Ball will give a good account of this species and its varia- 

 bility, lie has already proposed two varieties of it but has not yet 

 published decriptions of them. Therefore I had best refrain from men- 

 tioning the type specimen of one of his new varieties which I have seen. 



01. S. monochroma Ball in litt, — ? S. rotundifolia /5 ovata Nuttall, 



X. Am. Sylva, 75 (1843). — S. cordata Piper in Contr. U. S. N. at Herb. 



XI. 214 (I\ Wash.) (190G), pro parte — S, Machcnzieana Britton & Shafer, 

 Trees 19G (1908), pro parte. — S. pyrifolia Ball apud Coulter & Nelson, 

 New Man. Rocky Mts. Bot. 133 (1909), non Andersson. — This species 

 is in several respects a counterpart to S. mackcnzicayia. Specimens with 

 mature leaves are easily recognized by their greenish under surface. The 

 texture is thin compared witli that of the leaves of the following species. 

 In 1909, Ball referred to his pyrifolia the variety of Nuttall cited above, 

 but in the MS. -list Ball marks this name with a ?. According to Nuttall 

 it had been collected ''by the late Dr. Gairdener, on the hills of the Wahla- 

 met. " I have not seen the type specimen but from the description I 

 judge it should be regarded as the same as S, monochroma. 



The typical ^S. rotundifolia Nuttall has been considered by Ball (1909) 

 a synonym of Avhat he then called S. pyrifolia ohsciira. From Nuttall's 

 description I am inchned to take his rotundifolia for a form of S. myrtil- 



lifolia. Of Andersson's S. pyrifolia ohscura I have already spoken in my 

 note VII. on p. 169 in vol. i of this Journal. Since that was published I 

 have iiitiiii a sterile fragment of the type in Herb. Berol. (ex Herb. ^lus. 

 Bot. Stockholm). It consists of a i)iece of a branchlet with mature leaves 

 which are not quite concolor beneath, the ui)j)er ones being of a rather 

 lanceolate-elliptic shape, broadly cuneate at base, acuteat apex, somewhat 

 coarsely crenulate-dentate, and measure up to 7.5 cm. in length and 2.4-3 

 cm. in width, Tliey are glabrous on both sides except a sparse minute 

 pubescence on the midrib above and in the grove of the peti()U\s which 

 are about 15 mm. long. The stipules are semicordatc-lanccolate and 

 glandidar-serrate to dentate and 5 mm. long. According to Andersson 



thecapsalcs have shorter pedicels than those of ^S. pyrifolia. I am at present 

 unable to decide the question whether or not this var. ohscura Andersson 

 is a form of S. monochroma; but I am inclined to believe it may belong to 



