6 The AMERICAN BOTANIST 



necessary, therefore, to become acquainted with the plants in 

 the living condition. During the past year a considerable num- 

 ber of species showing markings of various kinds have been 

 observed, and the list could without doubt be considerably ex- 

 tended. 



It has usually been customary to ascribe some purposeful 

 effect or utility to the markings on the animal body and to the 

 fantastic patterns shown by many flowers. It is open to ques- 

 tion, 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 

 interesting material for the study of mutations and inherit- 

 ance. 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 pat- 

 tern. 

 3. Markings which are of more or less definite patterns 



not dependent on fundamental structures. 

 Under the first group mentioned above would fall such 

 forms as Phalaris arundinacea picta, already mentioned and 

 the numerous variegated species commonly cultivated in green- 

 houses. The white bands or spots being due to a lack of 

 chlorophyll in the parts. White stripes are frequently to be 



