1921] SCHNEIDER, NOTES ON AMERICAN WILLOWS, XII. 81 



occur rather frequently where the parents meet. See my note in Bot. 

 Gaz. lxvi. 335 (1918). 



S. Candida x S. cor data. The first mention of this hybrid is made 

 by Sargent in Gard. Chron. n. ser. x. 818 (1878) (see also Focke, Pflan- 

 zenmischlinge, 368 [1881]) who in a list mentions S. Candida x S. cordata 

 with the name S. rubella Bebb. I have not found this name rubella in 

 any of Bebb's writings, and it is not cited by Rowlee and Wiegand in 

 Bull. Torr. Bot. Club, xxm. 201, pi. 276, fig. 1, 14-17 (1896) who give a 

 good account of this hybrid. Bebb's name ought to be accepted for it. 

 For further information see also Sheldon in Bull. Geol. Nat. Hist. Surv. 

 Minn. ix. 585 (1896). 



S. Candida x S. petiolaris. This hybrid, too, was first mentioned so 

 far as I know, by Sargent in Gard. Chron. n. ser. x. 818 (1878), with the 

 name S. Clarkei Bebb (not S. Clarkii as printed 1. c. and also in Focke, 

 Pflanzenmischlinge, 368). According to Bebb's original notes published 

 by Rowlee and Wiegand in Bull. Torr. Bot. Club, xxm 196, the hybrid 

 was discovered by Daniel Clarke, M. D., in 1872 in Hascoll's Swamp, 

 near Flint, Mich. Rowlee and Wiegand give a good description of it. 

 According to Sargent, 1. c, Bebb also distinguished a var. subpetiolaris 

 and a var. subcandida of S. Clarkei. 



S. cinerea x S. discolor. Specimens taken by F. F. Forbes for this 

 hybrid do not represent such a cross and are nothing but the European 



5. nigricans Smith according to Toepffer, in litt. 

 S. Clarkei Bebb see S. Candida x petiolaris. 



S. coactilis X S. cordata. See Fernald in Rhodora, vn. 203 (1907). 

 S. cordata X S. discolor. As Bebb already stated in Gray, Man. ed. 



6, 482 (1890) hybrids between these two species may be met with where 

 the parents meet. 



S. cordata x S. glaucophylloides var. glaucophi/lla. See Toepffer, 

 Salicet. exsicc. fasc. vin. 298, no. 371 (1913). First distributed by 

 Forbes in sched. as S. cordata x glaucophylla . 



*S. cordata x S. incana. This very interesting hybrid between the 

 common east American species and the peculiar European S. incana 

 Schrank was found by W. R. Dudley in 1885 and distributed by him under 

 No. 857. See Dudley in Bull. Cornell Univ. n. 90 (1886). 



S. cordata x S. lucida. Distributed by F. F. Forbes in 1908 and also 

 mentioned by Knowlton and Deane in Rhodora, xvi. 108 (1914). It 

 seems rather doubtful to me. 



S. cordata X S. monticola. See Rydberg in Bull. Torr. Bot. Club, 

 xxxix 303 (1902). Rydberg regards as such a cross specimens from 

 Utah, Big Cottonwood Canyon, below Silverlake, where there is no true 

 S. cordata, and these forms need further careful observation. 



S. cordata x S. neo-Forbesii. First mentioned by Forbes in Rhodora, 

 xii. 10 (1909) as S. cordata x subsericea. See S. petiolaris x sericea. 



S. cordata x S. nigra. The nonexistence of such a hybrid I have already 

 discussed in my note xi in dealing with S. cordata. 



