AN OUTLINE OF PHYTOBIOLOGY. 11 



The classical work on locomotion of plants is Friederich 

 liildebrand's "Die Verbreitiingsmittel der PHanzen," 

 >frhe Dissemination-methods of Plants), published in 

 Leipzig, in 1873. This work sums up the subject most 

 admirably and is characterized by philosophical treatment, 

 richness in facts and judicious selection in ilhistration. 

 jSTo work has yet superseded it, and all students since its 

 appearance have based their studies upon it. I have 

 myself made free use of it in the preparation of this 

 l^aper. Darwin has much to say on this subject in the 

 ^'Origin of Species." Since then Hildebrand, Iluth, 

 MacLeod, and ver}^ many others have worked on 

 the subject. MacLeod has published a most useful 

 bibliography of publications on dissemination from 1873 

 to 1890 (in Botanish Jaarboek, Ghent, 1891.) Finally, 

 Kerner, in his " Pflanzenleben," (English translation by 

 Oliver,) has given us a most valuable though popular 

 discussion, richly illustrated, and Lubbock presents a 

 good summary in his " Flowers, Fruits and Leaves." 

 The present paper is designed not to describe the facts 

 ;already so well set forth in these works, but is an at- 

 tempt to reduce our knowledge of the subject to definite 

 principles which will make more easy an objective 

 knowledge of the subject and guide our local botanists 

 in further studies into the subject. 



II. Principles of the Modes of Locomotion of Plants. 

 I. Index)endent Aninuil-Like Mocei)ient, 



Since plants lack altogether muscular fibre, it is only 

 possible for independent automatic locomotion to occur 

 where the contractile power of the protoplasm itself can 

 be utilized. This occurs only in unicellular or very few- 

 celled organisms, i. e., only in the lowest and smallest 

 j)lants. Many of the lower algpe produce spores, (called 



