Rhododen- 
dron 
ferrugineum 
Rhododen- 
dron 
hirsutum 
16 ARBORETUM NOTES. 
ERICGAGE mm: 
According to Koch (Synopsis Florae Germanicae et 
Helveticae : Francofurti ad Moenum, 1837), a most 
accurate and valuable author—the ferrugineum be- 
longs more especially to the granitic Alps, the hirsu- 
tum to the calcareous portions of the chain. I have 
not had opportunity of verifying this remark to any 
considerable extent; but certainly where | have 
seen the /irsutum growing in abundance it was on 
limestone, on the calcareous Alps of the Bernese 
Oberland; and where I have seen the ferrugineum 
in most conspicuous profusion, was on the gneiss 
and mica schist of the main range (for instance, on 
the Simplon and Mont Cenis passes, and on the 
granitic rocks of the Mont Blanc group). On the 
Fura however, which is principally calcareous the 
hirsutum is the more rare of the two; Haller knew 
of only one mountain on which it grew. Both are 
found on the Bernese Alps, according to Mr. J. P. 
Brown, an excellent authority. 
On the Pyrenees, the ferrugineum is abundant, 
the hirsutum entirely wanting; but this is probably 
owing to some other cause than the nature of the 
rocks. 
RHODODENRON HIRSUTUM. 
Loudon, v. 2, 1137. 
See the preceding species. I observed that the 
hirsutum as it grows now in our garden, has its 
leaves rather narrower and less copiously fringed 
