Viialiiij and Organization of Protoplasm. 59 



agreement with the results recently attained on entirely different lines 

 of research, and will, moreover, contribute to render them intelligible. 



First let us face the problem of the specific interdependent localiza- 

 tion of the principal tissues and organs of organic individuals. As re- 

 gards this highly important question concerning the structural localiza- 

 tion and unity of composition of living animal beings, I will quote the 

 solution I ventured to advance as applied to inferior organism. This 

 i^olution will be found to flow naturally from the constitution and the 

 activities of the living substance, as explained in the former section. 

 The quotation is again from Mind, No. xx, 1880. "Here is a clear- 

 cut protoplasmic ovoid flowing evenly along, straight across the field of 

 the microscope. We will not let it slide by without closely scrutinizing 

 its activities; for, after closely examining them, it will seem as if this 

 morphologically undifferentiated organism had been made on purpose 

 to reveal to us the secret of tissue-formation. It embodies all the es- 

 sential traits of organization, but organization not yet structural ly_ 

 jSxed. Like our Paramtecium it also maintains a definite shape. It is 

 bilaterally symmetrical. It has an jpra l and an ahoyal pole, an incip- 

 ient integument and contractu layer, a digesting substance, a depurative 

 vesicle peculiarly situated. It takes food in only in front, retains it 

 until digested in the center of the body, and eventually evacuates the 

 residue at the aboral pole. There can be no doubt it constitutes a 

 complete organism with definitely determined positions of all its parts. / 

 Yet it can be readily ascertained that it consists, nevertheless, of noth- 

 ing but a fluent mass of molecularly coherent protoplasm. We have 

 here before us a single unit of living substance, fluent through and 

 through, and exhibiting, notwithstanding, a strictly localized distribu- 

 tion o f organic divisions and functions ; we have before us aLjjyino;^ vor- 

 tex, maintaining itself, and advancing head-foremost through space." 

 '^All the differently functioning regions of our vital vortex gain their 

 peculiarities merely from the special position which they occupy in the 

 chemical cycle that constitutes protoplasm. We have here, indeed, es- 

 sentially one and the same substance performing all the sundry organic 

 offices ; but it is by no means one and the same substance in one and 

 the same state of efficiency. It is a complex chemical circuit that gives 

 rise to the definite location of all the chief dift'erentiations of the or- 

 ganism; and it is the same substance at the different stages of this its 

 chemical circuit, which by means of its specifically changing relations, 

 becomes in turn the seat of all the main performances of vitality." 

 "The fundamental features of organization assumed by the living sub- 

 stance are the result of the same chemical cycle by which this very sub- 

 stance is itself formed and sustained." At trie time this view was ad- 

 vanced such a protoplasmic individual was believed to be throughout 

 composed of an aggregate of equal molecules ; and each part of it was 

 held to be indifferently capable of performing all vital functions. 



Visibly the living substance, when assuming the shape of a single pro- 

 toplasmic process or pseudopodium, forms then by force of its chemic- 



