88. Rhodora [May 
C. ALPINA L. Sp. Pl. i. 9 (1753). Cool woods, wet mossy openings, 
margins of streams, etc., southern Labrador to James Bay and north- 
westward to Alaska, southward through Newfoundland, eastern 
Canada, northern New England, northern New York, etc., and more 
locally to southern New England, Georgia, the Great Lake states, 
So. Dakota, etc.; also Eurasia. 
Gray HERBARIUM. 
IS ASTER TARDIFLORUS A HYBRID ? 
ARTHUR STANLEY PEASE. 
Durin the late summer of 1916, in the towns of Randolph, Gorham, 
and Jefferson, New Hampshire, I was on more than half-a-dozen occa- 
sions impressed by a blue-flowered Aster which I could not at once 
name. Its inflorescence at times suggested A. cordifolius, but the 
leaves were not cordate; the involucre was nearer to that of A. puni- 
ceus, but again the shape of the leaves failed to match. It was worthy 
of remark that the plant was in each instance solitary or appearing in 
but two or three specimens, while in each case A. puniceus and A. 
cordifolius were observed, usually in some abundance, near by. These 
facts led to the suspicion that one of the numerous hybrids of the 
genus had been found, and that A. puniceus and A. cordifolius, the 
two commonest and most generally distributed blue-flowered Asters 
of the region were its parents.' 
But my interest was further aroused when the plants in question 
proved, upon analysis, to match exactly the description in Gray’s 
Manual of Aster tardiflorus L., and when subsequent comparison 
at the Gray Herbarium confirmed this diagnosis. The query, then, 
naturally arises whether A. tardiflorus is not a hybrid. Its intermedi- 
ate characters can be more clearly indicated by the following résumé 
(compiled from the Manual descriptions of the three species I have 
mentioned ).? 
! The only other blue-flowered Asters known in the region are A, macrophyllus L., A. radula 
Ait., A. foliaceus Lindl., and A. novi-belgit L. The first two of these bear no resemblance to the 
plants in question, and the last two are of very local distribution and unknown in the neighbor- 
hood of most of the stations for the supposed hybrid. 
? Points not noted in the Manual are enclosed in brackets. 
