114 
IOWA ACADEMY OF SCIENCES. 
Helianthus annuus L. Ames and other parts in central Iowa 
occasional, but in western Iowa indigaaous and very abundant, 
becoming frequent as far as Carroll, Denison and Boone. 
Ames, 1882. It is scarcely abundant except in a few localities 
in central Iowa. I am inclined to think it is an introduced plant 
with us. Boone, 1871 (C. E. Bessey). Grinnell, 1891 (M. E. 
Jones). Keokuk, 1891 (P. H. Rolfs). Muscatine, 1891 (Rep- 
pert). Marshalltown, 1891 (F. C. Stewart). 
Helianthus maximiliani Schrad. Indigenous to northern and 
western Iowa, confined originally in western part of the state 
to the loess hills and adjoining bottoms, but now occurs along 
some of the great trunk lines extending across the state. A 
sm.all patch has persisted at Ames for several years. 1894 (G. 
W. Carver). 
Gaillardia aristata Pursh. This western plant has been found 
at Ames, 1896 (G. W. Carver). Too soon to say whether it will 
become naturalized. 
Dysodia cJirysanthemoides Lag. Boone, 1890. Ackley, 1878 
(B. E. Canavan), Keokuk, 1891 (P. H. Rolfs). Muscatine, 1891 
(F. Reppert). This striking weed has been known for some 
time at Ames, though said to be frequent by Hitchcock (Anth. 
Pteridophyta of Ames, p. 503). It is more or less periodic in its 
appearance, some years frequent, others it is not so common. 
It is, however, always abundant in w’estern and southwestern 
Iowa, which leads me to believe that the plant is not indigenous 
to central Iowa, but introduced, although now occurring in 
timber and along river banks. 
Anthemis cotula D. C. This European weed is by no means as 
common in dooryards, along. roadsides and in streets as in Wis- 
consin, Illinois and Minnesota. It shows evidence, however, 
of being widely distributed in the state, and early introduced. 
Chrysanthemum leucanthemum L. For a long period of years 
occasional specimens of this weed have been found in the 
vicinity of the college, and it is an occasional introduction in 
meadows, but except in one place some four miles from Ames it 
shows no evidence of being naturalized. It has also been 
reported from Muscatine (Reppert). Atlantic (S. O. Hamill). 
Ames, 1871 (C. E. Bessey). Ames, 1891 (P. H. Rolfs). Shel- 
dahl, 1885 (L. V. Harpel). Ackley, 1878, (B. E. Canavan). 
Tanacetum vulgare L. Although escaped here and there 
from gardens there are but few places where it is naturalized. 
Cnicus lanceolatus Hofim. This is a frequent weed, especially 
eastern, southern, northern, western and central portions of the 
