4 ELEVENTH REPORT. 



Economically, the study of unicellular life has made itself felt in general 

 ])iological studies. It has thrown light upon many of the phenomena of 

 life which, heretofore, were not well understood, and has added many new 

 biological discoveries, largely because the cell was more basic and more 

 simple; thus, more susceptible to ready solution. Mere mention can be. 

 made of a very few of these matters in this cursive presentation, but even 

 this must lend concreteness and force to the importance of such contribu- 

 tions. The impetus given to the study of fermentation and diseases by 

 Pasteur and the interpretation of them have in one way and another initiated 

 a new regime in the field of biology. The work of Metchnikoff with phago- 

 cytes has not only been the means of centering considerable attention and 

 effort upon these cells and their functions, but has caused a more exhaustive 

 study of blood corpuscular elements, so that today the knowledge thus 

 acquired shapes itself into a dignified branch of science which is of great 

 usefulness. The study of toxins by Koch, Kitasato, and Von Behring 

 has stimulated others to activity in similar lines in the field of botany and 

 zoology. With the advent of Roux, Ehrlich, and many others, in their 

 most skilful studies of anti-toxins, old notions of vital cellular and molecular 

 reactions were swept away and new ones substituted. Out of these investi^ 

 gations, the blood reactions, emanating from a knowledge of agglutinins and 

 similar bodies possessing specific action, have extended the field of general 

 biological knowledge. Many illustrations of kindred lines of development 

 may be cited to indicate the trend of unicellular studies, but these will 

 suffice for our purpose, inasmuch as they point to the molecular interpre- 

 tation of cell activity. 



We pass now from a more general to a more intimate characterization of 

 our subject and our thoughts will center upon the cell. Two distinct lines 

 of thought arise for consideration in bringing unicellular hfe forms into 

 relief for the purpose of discussing their relation to life's beginnings. The 

 one, the functional, which in our interpretation will be regarded as basic; 

 the other, the structural, or morphological, which will be regarded in a 

 large measure dependent upon the functional. By these two concepts 

 everything utilized in this paper will be measured, because most ideas bearing 

 upon this subject will fall readily into one of the two classes. 



It is custon'iary to deal with the structural cytology of micro-organisms 

 before designating the physiology, but for the present I desire to reverse 

 this in order to make the arrangement more logical. 



t Protoplasm, if regarded in its broadest sense, may be regarded, notwith- 

 standing its indefiniteness, as the common basic substance of cell life and 

 structure. As to its nature, no nearer approach is made to its analysis than 

 through its physical and chemical aspects. We cannot, however, enter 

 upon such a discussion successfully unless we review concisely the jsresent 

 status of "Spontaneous Generation" in its relation to the origin of hfe, for 

 this must be the final thought of every listener, although it will ever be just 

 over the l^order or beyond his reach. Leeuwenhoeck first saw micro- 

 organisms in 1675. Previous to his time, and for many years after, it was 

 believed that life could in some way be produced from dead or inert matter. 

 Needham in 1749, announced that he had succeeded in securing the 

 spontaneous development of life in beef broth, which had been boiled and 

 stored in a flask. Spallanzani, in 1765, demonstrated that Needham's 

 work was ineffective, because he had not observed proper precautions in 

 sterilizing and handling the flasks. Spallanzani, through proper precautions, 

 succeedecl in retaining his beef tea sterile or free from germ development. 



