260 The Unity of the Organism 



(b) Structure of the Inner Portion 



* 



Wc now pass from the consideration of the peripheral 

 parts of the bacteria to an examination of the internal body 

 mass. Recent discussion of this subject having been mostly 

 carried on from the elementalist standpoint, with either nu- 

 cleus or chromatin as the guiding star, gives the distinct 

 impression of having for its end not full and accurate de- 

 scription of anything and everything that exists in the 

 organism, but proof that a nucleus or chromatin either do 

 or do not occur there. Writings under this head are so 

 numerous and voluminous as to make a comprehensive re- 

 view out of the question, and the diversity of opinion is so 

 great and so strenuously set forth in some instances as to 

 make satisfactory judgment of just what has been found 

 difficult. The one thing that stands out with great clear- 

 ness in the illustrations and descriptions of such recent 

 works as those of Biitschli, Schaudinn, Arthur Meyer, Guil- 

 lermond, Menol, Ruzicka, Swellengrebel, and Dobell, is that 

 the main body substance of the organisms is far from homo- 

 geneous. A considerable variety of objects are undoubtedly 

 differentiated within the protoplasm. Difference of opinion 

 among the latest investigators concerns only the nature of 

 these objects. Perhaps the most generally observed differ- 

 entiations are granules of various sizes, shapes and behavior 

 toward stains. The next most common structures seem to 

 be networks and strands of varied character. The mate- 

 rials of these appear to differ generally from those of the 

 granules in "taking" stains with less avidity. Vacuoles are 

 another type of structure which present-day methods are 

 discovering to play an important part in these minute or- 

 ganisms, as they have long been known to do in many pro- 

 tozoa, and in the cells of higher plants. 



The narrower needs of our undertaking do not require us 

 to examine farther these internal parts. The bare fact of 



