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IOWA ACADEMY OF SCIENCE Vor. XXIX, 1922 
number of heads per plant ranged from one to ninety, with an 
average of nine heads per plant. 
Next, the number of seeds produced by a head on the Common 
Dandelion was compared with those produced by a head on the 
Red-seeded Dandelion with results as follows : The seeds were 
counted on 23 heads of each species. The number of seeds on 
the Common Dandelion heads ranged from 84 to 282 with an 
average of 190 per head. With the Red-seeded species the num- 
ber ran from 71 to 182 with an average of 107. 
These averages multiplied by the average heads per plant give 
a comparative ratio of 1900:969 or about 2:1 in favor of the 
Common Dandelion. It is noticeable that the Common Dandelion 
makes a much ranker growth than the Red-seeded species and 
that it seems to stand competition of tall growing grasses much 
better than its relative. The Red-seeded one seems to prefer 
shady places where there is scarcity of grass, also a sandy soil. 
As is well known, the Common Dandelion will grow anywhere. 
The Red-seeded variety seems to appear earlier than the common 
variety as on the former plants scarcely any flowering buds or 
flowers were present at the time of examination but an abundance 
of seed heads was found. The color of the flowering heads of 
the two varieties differs somewhat in that the head of the Com- 
mon Dandelion is a brighter golden yellow while that of the Red- 
seeded species is a darker orange yellow. But this difference is 
not marked unless flowers of each are held together and examined. 
No difference in the root system could be found except that the 
roots of the Common Dandelion seemed more brittle and less 
easy to dig out of the ground than the roots of the Red-seeded 
Dandelion. This, however, does not appear to be a constant 
difference. 
Upon investigation of the bracts of the involucre of both species 
it appears that the Common Dandelion bears more bracts to the 
head. They are tinged with a dark green and curled downwards 
while the bracts of the Red-seeded species stand straight out 
prominently, are tinged with red and the involucre, on the whole, 
is glaucous. 
Effort was made to find some constant difference in the leaves 
but no conclusion could be reached in this respect. Large numbers 
of leaves of the two species were collected, pressed and compared. 
It was found that the leaves of the Red-seeded Dandelion average 
more deeply cut while those of the Common species are more nearly 
