Dec., 1910.] Leaf Markings of Certain Ohio Plants. 
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LEAF MARKINGS OF CERTAIN OHIO PLANTS.* 
John H. Schaffner. 
Among the most familiar objects of our fields and gardens are 
such plants as the red and white clover with definite light-colored 
markings on the leaflets. Another equally prominent plant in 
gardens is the ribbon-grass (Phalaris arundinacea picta), whose 
leaves show variegated longitudinal bands of white and green color. 
Sometime ago the writer began to collect data on the native 
and introduced plants of Ohio which show any definite type of 
markings. The problem is rather difficult since the markings 
usually disappear when plants are dried. It becomes necessary, 
therefore, to become acquainted with the plants in the living 
condition. During the past year a considerable number of 
species showing markings of various kinds have been observed, 
and the list could without doubt be considerably extended. 
It has usually been customary to ascribe some purposeful 
effect or utility to the markings on the animal body and to the fan- 
tastic patterns shown by many flowers. It is open to question, 
however, whether such an assumption should be generally applied. 
The markings on the leaves of plants are favorable objects in this 
connection and may throw considerable light on the subject. 
In many species, certain individuals have the markings while 
others lack them. There are probably elementary species present 
which might be segregated. These forms should make interest- 
ing material for the study of mutations and inheritance. In some 
species the markings are only on the younger leaves, in others only 
in connection with the inflorescence and thus on the latest leaves 
to be developed. 
The markings of the leaves studied may be grouped under 
three general heads as follows: 
1. Markings due to abnormal or diseased conditions, or 
the so-called variegations. 
2. Markings more or less accidental, depending on some 
internal structure and evidently having no relation 
with the development of a definite pattern. 
3. Markings which are of more or less definite patterns 
not dependent on fun dimental structures. 
Lender the first group mentioned above would fall such forms 
as Phalaris arundinacea picta, already mentioned and the numerous 
vairegated species commonly cultivated in greenhouses. The 
white bands or spots being due to a lack of chlorophyll in the parts. 
White stripes are frequently to be observed in young plants of 
corn, Zea mays, and occasionally the entire plant is white. These 
latter individuals usually do not survive long. 
* Read at the meeting of the Ohio Acad, of Sci., Nov. 2o, 1910. 
