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AMERICAN BIOTIAN STUDIES T7 
able" ; but he did not publish till 1836, “ waiting," with unusual 
reticence, “ to see what De Candolle and Torrey will do." * When, 
in 1836, he published his long-delayed remarks on Aster and 
Solidago, he observed (New Flora, 7) that ‘many species of 
Aster and Solidago are found chiefly in October, and therefore 
had escaped the attention of our botanists, who chiefly botanize 
or travel in the summer." But even this year, in revising the 
Compositae, Rafinesque states that he is “leaving most of the As- 
ters for further inquiries" ; which explains why this genus is not 
more complicated by synonyms of his introduction. As it is, he 
had determined on the separation from Aster (his Asteriscus) of 
several new genera. One of these was to contain the Biotian 
Asters ; he called it Letachenis, characterizing it by having smooth 
achenes and simple pappus. Under this in a subgenus Dodecalis 
he proposed to class the species with appressed bracts and about 
I2 rays; which was to include the Biotian plants, “A. corymbosus,” 
as he says, etc.; but was also to include such dissimilar species as 
A. dumosus, and illustrates the danger of relying on a single 
character. 
At about the same time with Rafinesque's beginnings, or by 
1809, Muhlenberg, with his usual careful observation, had collected 
the plants of southeastern Pennsylvania, and seems to have been 
the earliest to take notice of A. umbelliformis, which the fragments 
of his herbarium include as one of his unnamed forms of “ A. 
corymbosus." 
Barton, who in addition to A. macrophyllus and A. divaricatus, 
had made known his variety a/atus of the latter as early as 1815, 
seems to have been the first recorded as watching an Aster colony 
for several years to determine its normal range of variation. It 
was in that way that he satisfied himself that his variety alatus was 
genuine, 
Slightly later, some new forms appear in American descrip- 
tions ; A. riciniatus may have been what Elliott described as A. 
corymbosus, about 1824; A. tanthinus that which Bigelow, also 
1824, described as 4. macrophyllus ; A. orbicularis and securi- 
formis seem to have been collected under the latter name by 
* Rafinesque, New Flora, part 4, page 69. 1836. 
