SOME UNSOLVED SCIENTIFIC PROBLEMS 



take that final logical step which to-day's knowledge 

 foreshadows as a future if not a present necessity. 



The Mechanism of the Cell 



Whatever future science may be able to accomplish 

 in this direction, however, it must be admitted that 

 present science finds its hands quite full, without going 

 farther afield than to observe the succession of gen- 

 erations among existing forms of life. Since the es- 

 tablishment of the doctrine of organic evolution, ques- 

 tions of heredity, always sufficiently interesting, have 

 been at the very focus of attention of the biological 

 world. These questions, under modern treatment, 

 have resolved themselves, since the mechanism of 

 such transmission has been proximately understood, 

 into problems of cellular activity. And much as has 

 been learned about the cell of late, that interesting 

 microcosm still offers a multitude of intricacies for 

 solution. 



Thus, at the very threshold, some of the most ele- 

 mentary principles of mechanical construction of the 

 cell are still matters of controversy. On the one hand, 

 it is held by Professor O. Butschli and his followers 

 that the substance of the typical cell is essentially 

 alveolar, or foamlike, comparable to an emulsion, and 

 that the observed reticular structure of the cell is due 

 to the intersections of the walls of the minute ultimate 

 globules. But another equally authoritative school of 

 workers holds to the view, first expressed by From- 

 mann and Arnold, that the reticulum is really a sys- 

 tem of threads, which constitute the most important 

 basis of the cell structure. It is even held that these 

 v.-is 225 



