32 Mr. Tuckerman, on some Plants of New England. 
Aunus.—Instead of one, there are three very different Alders 
in New England. The following account of them will, it is 
hoped, be found accurate. 
A. incana, (Willd.): foliis submembranaceis oblongis acutius- 
culis basi obtusis s. cordatis margine sublobatis argute serratis sub- 
tus glaucis pubescentibus venis hirsutis axillis venarnm nudis, 
amentis foemineis ovalibus, stipulis oblongo-lanceolatis. KE. 'T.— 
Betula incana, L. Suppl. A\7. Alnus incana, Willd. Sp. 4, 335, 
Muhl. Catal. p. 89, Hook. Bor. Amer. 2, 157, ( part.) —A. glau- 
ca, Michx. f. Sylv. 1,379, Oakes, Catal. Verm. p.25. A. crispa, 
Pursh, Fl. 2, 623. (part., non Miche. nec Gray.) | 
Hab. ‘‘ New Hampshire and Vermont. Unknown in the South- 
ern, and rare in the Middle States,” Michaux f. Pokono Mountain, 
Pennsylvania, Pursh, in herb. Lambert. . Pennsylvania, Muhlen- 
berg. Massachusetts, and northern parts of New England, as at 
Cambridge, Woburn, Framingham, Ipswich; and exceedingly 
abundant about the White Mountains; Oakes, E. T. The 
Alnus glauca of Michaux’s Sylva, though a very abundant spe- 
cies at the north, seems to have been neglected by botanists, 
and is hardly to be found mentioned in our manuals. By the 
leaves it is easily distinguishable from A. serrulata, and is besides 
commonly taller, so as sometimes to become asmall tree. Ihave 
a specimen from the Lambertian herbarium, ticketed by Pursh 
“ Alnus crispa, July 25, 1808, Pokono,”* which is perhaps the A. 
incana of Muhlenberg’s catalogue, and is certainly only a stunted 
form of the present species. ‘The shrub is rare, according to 
Michaux, in the Middle States, and possibly is there found only 
on the mountains. 
Our species seems too near to A. incana to be kept separate. 
The leaves agree perfectly well with those of my foreign speci- 
mens of the latter, while that has been recognized as American 
by Muhlenberg and by Hooker. 
A. rnuBra, (Marsh.): foliis subcoriaceis obovatis acutis argute 
serratis venis axillisque venarum villosis, amentis foemineis ova- 
to-oblongiusculis, stipulis ovalibus obtusis. E. T.—Betula Al 
nus, Clayt. §* Gronov. Fl. Virg. edit. 1, p. 115. B. peduncu- 
lis ramosis, Sc. Clayt. § Gironov. Virg. edit. 2, p. 146. Betula- 
*It appears that ‘ incana’’ had originally been written on this ticket, but it is 
crossed out, and crispa written over. And Michaux, after the description of his 
Alnus glauca, adds the synonym, “ A. incana, Willd.” 
