COROLLA-CHARACTERS 43 
the branches usually have no rameals except as branchlets are 
produced, and are subtended by these bracteals. In the Curves- 
centes and in A. Claytont and relatives, a very peculiar habit of 
growth occurs, a pair of nearly opposite bracteal leaves occurring 
on the exterior branches at about two-thirds the distance toward 
the last branchlet. In long branches sometimes several additional 
bracteals follow ; so also in A. macrophyllus apricensis. At least 
a pair of such bracteals, but alternate or at least less closely 
opposite, occur usually in longer branches of A. macrophyllus, 
A. roscidus, A. multiformis. Other asters are apt to have a num- 
ber of much reduced bracteals on a branch, not simply a pair. 
Number of rays: fairly constant within narrow limits ; certain 
forms of A. divaricatus producing 5 or 6, others 6—9 rays; in the 
five-ray form largely 5, in the Trientalis form largely 7; in A. 
Claytont 6 ; in the Curvescentes about 10; in the Macrophylli about 
I3; in A. nobilis apt to be 11; in A. violaris up to 15 or more; 
the highest number produced in any frequency in a Biotian aster 
seems to be about 20, doubled by A. Novae-Angliae, and some- 
times so by forms of A. Novi-Belgit. 
Numbers of disk-flowers : less often tested, and subject certainly 
to somewhat wider latitude ; but within those wider limits seems 
fairly constant. The green-disk form of A. divaricatus is perhaps 
the minimum, with 4 disk-flowers repeatedly ; full disks show 
20-25 (A. tenebrosus) and maximum disks 50 in A. macrophyllus, 
A. roscidus, etc. 
Number of nerves in each ray 5 and with little variation ; so of 
the 5 lobes of the disk flower. 
Number of teeth terminating the ray 2 usually, in the Divaricat 
and Curvescentes, but with many exceptions, broad-ray forms 
being likely to have 3, and some forms more. The number is rather 
characteristic within the species, but not wholly so. In the Macro- 
PÀyll it is more regularly 3 ; in A. modilis, none at all, and with 
Sharp apex ; in A. excelsior, none, with rounded spatulate apex. 
Depth of disk-lobes is a moderately permanent character; the 
remainder of the disk-body is twice that depth in most Macro- 
phylli, little more than equal to it in A. Jussiet, A. nobilis, A. 
decaphyllus, etc., three times the depth in A. Claytoni and perhaps 
four times in A. Ed De) Disk-lobes divided nearly through- 
