Opors 33 
to be the same as that which is developed in the rays; as in 4. vio- 
laris, A, tostemma, etc.; and, with less violet, in A. macrophyllus 
and many others. On the same plants the glands of the under- 
side of the leaf, where they exist, are of a different and lighter 
color, from whitish (as A. zanthinus) to straw color (A. roscidus), 
FRAGRANCE 
At least six kinds of fragrance occur among Biotian asters, 
some of which are quite persistent through the species in which 
they occur. 
I. Bee-bread odor, in the disks, strongest when their color- 
change is about half accomplished, when a luminous warm sienna- 
brown has succeeded the yellow preliminary to the full reddening. 
The pollen-masses are at this time opening, and insects arriving. 
The odor is rather difficult to define by parallel, but is quite simi- 
lar to that of bee-bread in the cells of the common bumblebee. It 
appears not much developed in asters outside the Biotian group, 
but it is very common in Solidago, especially S. serotina, and 
S. gigantea, and in many other flowers, in early anthesis. I have 
observed it highly developed, among Biotian Asters, in A. /zfez- 
mis, A, roscidus, A. ianthimus, considerably so in A. violarts, 
A. quiescens, A. Clayton, A. uniformis, moderately so in A. multi- 
formis, A. macrophyllus ; also in A. ardens; so so in A, 
divaricatus, at least in many instances. 
.2. Nutty odor; derived from the glands, an odor somewhat 
as of walnuts, especially of the glands of Juglans nigra and of 
Hicoria tomentosa. Many glands widely diffused through the 
vegetable kingdom diffuse this odor, which is subaromatic—but 
very different from the aromatic odor of broken magnolia leaves ; 
equally different from the more typical aromatic odors of spices 
and not at all to be confused with the anisate odors of Arala ` 
racemosa and many Umbellifers. Of this nutty odor familiar exam- 
ples among asters are A. /Vovae- Angliae, A. oblongifolius, A. gran- 
difforus; among Biotian asters A. roscidus shows it in highest 
degree, sometimes equal to A. Novae-Angliae. It is perceived in 
those two species on approaching within a few inches of the pedicels 
or bracts, where the odorous glands are particularly numerous. It is 
faintly perceived in the same way in A. zanthinus, and A. Herveyi, as 
