290 AMERICAN MIDLAND NATURALIST 
involucres and peduncles with longer hairs, achenes 6 mm. long, 
light brown, and pappus shorter than the achene; and from 
C. denticulata Rydb. by its small size, small obovate leaves and 
smaller solitary involucres, 1 cm. high or less. 
The plant grows in wet soil and is represented in my herbarium 
from many different localities, but shows invariably a remarkable 
regularity in characters, with exception of two occasional forms. 
One of them, found at Pleasant Lake, with large leaves and long 
petioles, has involucres with scanty and almost glandless hairs; 
the other, from the shore of Lake Ibsen, has long, glandless hairs, 
on the petioles and midribs of the leaves. As type has been selected 
a specimen consisting of plants collected by the writer at Butte, 
Benson County, on June 27 and July 16, 1912. 
Leeds, North Dakota. 
WESTERN MEADOW RUES.—I. 
BY EDWARD L. GREENE. 
The species of Thalictrum in the Middle West do not appear 
ever to have been made the subject on any critical study by any 
one anywhere hitherto. In that whole great field, the utmost 
that has been done has been the collecting of fragments for the 
herbaria, and sending them forth labelled, some T. dioicum, 
some T. polygamum, and some T. purpurascens, but it is almost 
a rarity to find any one of those names correctly applied; or, if 
one must make an exception to that statement in the case of the 
name 7. dioicum—a group easily recognized—the two other names, 
according to the showing which all our herbaria make, are much 
more often incorrectly assigned than correctly. 
When I speak of herbarium fragments as being about all 
that we at the East have for light and guidance on the subject 
of the meadow rues of the prairie regions, I am not saying that 
the specimens are small. The fact is that many of them are so 
large as to fill an herbarium sheet of standard size; but if a plant 
is six feet high, or even four, and only the mere top of it, with 
its flowers or fruits taken, that specimen, though it measure ten 
inches across and fifteen inches lengthwise, is still but a fragment, 
and wholly inadequate to the determination of the species, for 
