CH. IV] INTERNAL FORM AND STRUCTURE OF CELL L57 



has been often easier to attribute virtues than to ascribe intelligible 

 functions or modes of action. But here and there nevertheless, 

 throughout the whole literature of the subject, we find recognition 

 of the inevitable fact that dynamical problems lie behind the 

 morphological problems of the cell. 



Blitschli pointed out forty years ago, with emphatic clearness, 

 the failure of morphological methods, and the need for physical 

 methods, if we were to penetrate deeper into the essential nature 

 of the cell*. And such men as Loeb and Whitman, Driesch and 

 Roux, and not a few besides, have pursued the same train of 

 thought and similar methods of enquiry. 



Whitman!, for instance, puts the case in a nutshell when, in 

 speaking of the so-called " caryokinetic " phenomena of nuclear 

 division, he reminds us that the leading idea in the term " caryo- 

 kinesis'' is motion, — "motion viewed as an exponent of forces 

 residing in, or acting upon, the nucleus. It regards the nucleus 

 as a seat of energy, which displays itself in -phenomena of motion J." 



In short it would seem evident that, except in relation to a 

 dynamical investigation, the mere study of cell structure has but 

 little value of its own. That a given cell, an ovum for instance, 

 contains this or that visible substance or structure, germinal 

 vesicle or germinal spot, chromatin or achromatin, chromosomes 

 or centrosomes, obviously gives no explanation of the activities of 

 the cell. And in all such hypotheses as that of "pangenesis," in 

 all the theories which attribute specific properties to micellae, 



* Entwickelungsvorgdnge der Eizelle, 1876; Investigations on Microscopic Foams 

 and Protoplasm, p. 1, 1894. 



t Journ. of Morphology, i, p. 229, 1887. 



J While it has been very common to look upon the phenomena of mitosis as- 

 sufficiently explained by the results towards which they seem to lead, we may iind 

 here and there a strong protest against this mode of interpretation. The following 

 is a case in point: "On a tente d'etablir dans la mitose dite primitive plusieurs 

 categories, plusieurs types de mitose. On a choisi le plus souvent comme base 

 de ces systemes des concepts abstraits et teleologiques : repartition plus ou moins 

 exacte de la chromatine entre les deux noyaux-fils suivant qu'il y a ou non des 

 chromosomes (Da.ngeard), distribution particuliere et signification dualiste des 

 substances nucleaires (substance kmetique et substance generative ou hereditaire, 

 Hartmann et ses eleves), etc. Pour moi tous ces essais sont a rejeter categorique- 

 ment a cause de leur caractere finaliste ; de plus, ils sont construits sur des concepts 

 non demontres, et qui parfois representent des generalisations absolument erronees." 

 A. AlexeiefE, Archivfitr Protistenkunde, xix, p. 344, 1913. 



