29 PITTONIA. 
NOTES ON MACHjERANTHERA. 
At page 60 of the preceding volume I named, and gave an 
outline of the characters of M. montana, recording at the 
same time my suspicion that it would be found an aggre- 
gate of several good species. Since the time of that writing 
I have again visited the habitats of several of these plants; 
have also examined, in the herbarium of Columbia College, 
several of Nuttall's specimens not seen by me before; and 
lastly, Professor Nelson of the Wyoming University has 
sent me coplous material from those high plains where 
Nuttall himself collected so long ago. I am thus much 
better equipped than I was three years ago, for the work of 
identifying, and more fully describing certain of Nuttall's 
Dieterias, most of which fall, according to my view, into the 
genus Machzranthera. 
M. viscosa. Dieteria viscosa, Nutt. ‘Trans. Am. Phil. Soc. 
vii. 301. M. montana, Greene, Pitt. iii. 60, in part. Bien- 
nial; the stems solitary or several, erect, 1 to 2 feet high, 
usually spieate or racemose in the middle, but more corym- 
bose at summit, or not rarely wholly eorymbose: herbage 
green and seemingly glabrous, but under a lens puberulent, 
the inflorescence and especially the involueres glandular and 
viscid: lower cauline leaves narrowly oblanceolate. rather 
remotely but sharply serrate: bracts of the large and nearly 
turbinate involucre in 5 or 6 series and closely imbricated, 
their green herbaceous tips long and narrow, closely reflexed 
and very viscid: rays rich purple, 18 or 20: achenes much 
compressed, the faces rather obscurely striate under the thin 
coat of appressed silky pubescence. 
Plentiful on plains of the Platte in northern Colorado; 
the above description based on specimens collected by my- 
self at La Salle, in 1896. The herbage is, as Nuttall said, 
fragrant; the odor balsamic and very pleasant. 
