1920] SCHNEIDER, NOTES ON AMERICAN WILLOWS. IX 11 



beneath with a minute brown pubescence " while of S. flavescens Nuttall 

 states: " For a good while the leaves still remain downy, particularly on the 

 under surface, which is tinged also with pale yellow." After all, however, 

 I cannot find that both kinds of pubescence indicate two really different 

 f(jrms because in several specimens before me the older (lower) leaves agree 

 with the description of S. stagnalis, while the younger (upper) leaves have 



the pubescence of S. flavescens. 



Among the specimens from the Yukon Territory there are some with 

 very tomentose branchlets of the preceding year of which the (not yet 

 quite matiire) leaves bear a thick soft pubescence on the lower surface. 

 On other specimens the pubescence of the branchlets seem to disappear, and 

 the leaves soon become glabrescent while, too, there are forjus with quite 

 glabrous branchlets of the previous year and with quickly glabrescent 

 leaves which finally show only a thin pubescence of minute gray and brown- 

 ish hairs on the lower surface. 



The extremes of those forms are indeed very unlike each other, but there 

 are apparently many intermediates between them. Henry expressly states 

 that the leaves " in moist situations often remain tomentose beneath, in 

 drier becoming silky and finely brown beneath." Piper, already in 1906, 

 emphasized the fact that S. Scoulcriana is " an exceedingly variable spe- 

 cies as to foliage and habit, but in the floral characters apparently not 



capable of being divided." 



The main variation in the female flowers is in the length of the style which 

 mostly is somewhat hairy, and in the length of the stigmas which varies 

 from 1 to 2 mm. We do not yet know whether these variations correspond 

 with others in the leaves or in other parts of the plant. Sometimes the pedi- 

 cel is as long as the bract, but there is no other indication of an influence 

 of S. Bebhiana. The male flowers seem normally to have glabrous fila- 

 ments or rarely a few hairs at their base. Whether forms with filaments 

 hairy up to half of their length (which seems to be often the case with late 

 flowers) can be separated I have not been able to make out. Of Die color 

 of the anthers Miss Eastwood says in a field note of the Yukon forms : 

 " Some bushes have yellow anthers and some have red. The former have 

 yellow catkins before the anthers open and the latter red. The same dif- 

 ference in color holds in the pistils." I have never seen purple anthers in the 

 forms of other regions except in one specimen (L. E. Smith, no. .574) from 



Sisson, California, 



At present I do not retain more than two varieties of S. Scouleriana. One 

 is the tyi^e (S. brachystachys Scouleriana tenuijulis Andersson) apparently 

 figured by Sargent (Silva, t. 482) which according to the type specimen is 

 characterized as foflows: raraulis floriferis dense villosulo-tomentosis, foliis 

 juvenilibus di:.tincte ferrugineo-pilosis, amentis femineis submaturis circ. 

 3^ cm. longis, circ. 12 mm. crassis, ovariis stylo circ. 0.5 mm. longo plus- 

 minusve distincto, stigmatibus siccis circ. 1 mm. longis, pedicellls glandulam 

 2-plo superantibus, circ. 1.5 mm. longis, fructibus maturis circ. 6-7 mm. 

 longis. As to the leaves I can only say that while they seem to become very 



