767 



P. trichocarpa. Hook. ; Sargent Silva of North America 

 t. ViW. Western North America. '' Black Cotton- 

 wood," 



P, balsamifera var. trichocarpa, S. Wats. 



P. tristis, Fisch. ; Dippel Laubholzk. ii. 205, f. 98. North- 

 eastern Asia. 



Var. elongata, Koeline. 



P. candicans elongata, Dippel. 



P. Viadri, J/. Ruedigrr. Origin uncertain. 



P. Wobstii, ScJiroeder. Garden origin ? 



F. balsamifera far. Wobstii, Dippel Laubholzk. ii. 2'>7. 

 f. 101. 



Empetraceae. 



Empetrum nigrum, L. ; Eng. Bot. ed. H, t. 1251. North 

 temperate and arctic zones. " Crowberry." 



E. crassifolium, Rafin^ 



E. procumbens, L. 



Var. scoticum, Loud. 

 E. scoticum, Hooli. 



Var. tomentosum, Dippel. 

 E. tomentosum, Rort. 



Corema album, D. Don : Laguna Fl. For. Esp. ii. t. 17. 

 I'ortugal. 



Empetrum lusitauicum. Hurt. 



C. Conradii, Tor/:; Britt. & Br. Illust:-. Fl. ii. ;!S]. f. 

 Northern United States, &c. 



Empetrum Conradii, Tor/: 



