250 XA PITTONIA. 
diagnosis, is its fastigiate branching, by virtue of which the 
full-grown plant is more or less approximately flat-topped, 
none of the branches being horizontally directed, but all 
strongly ascending. And I have not sought in vain for a 
mention of the mode of branching of B. frondosa by early 
writers. Philip Miller, in the year 1759, speaks of the 
plant familiarly, after having grown it for many years, as 
“sending out many horizontal branches;" another most 
decided testimony in favor of the freely and widely branch- 
ing B. melanocarpa as being the true B. frondosa. 
So then, the B. frondosa of Linnsus, according to the 
testimony of a long line of descriptive witnesses, had the 
following four elear marks of identity with what has now 
been called a new B. melanocarpa: (1) Its branching was 
horizontal; (2) Its heads were radiate, and otherwise so 
yellow in appearance that it was early called a Chrysanthe- 
mum; (3) Its heads were not notably larger than, nor dif 
ferent in form from, those of B. tripartita; (4) Its achenes 
were black, or nearly so. In none of these points is my 
B. vulgata at agreement with this actual B. frondosa of seven- 
teenth and eighteenth century authors; therefore it must 
be that real segregate, which was so long awaiting recog- 
nition. 
As to Mr. Wiegand’s variety, which I may designate as 
B. vulgata var. puberula, I have seen and collected it more 
than once, as often wondering if it might not prove 
specifically distinct, but have not yet found characters to 
warrant the proposition. I can not but suspect, from the 
comparative scareity of B. vulgata at the East, that it came 
originally from the prairie States, and is not indigenous 
with us here. Its habitat in the vicinity of Washington is 
cultivated ground almost or quite exclusively, which is far 
from being the case with true B. frondosa. 
