J'h'<)IJI/:U.\T/(>\ AM) h'KdENERATION 



283 



SO;, is from 0.6-1.2 per cent. Chlorine is about the same in botli 

 forms. These differences are, however, not as constant as Bamberger 

 believes, aecordino- to several later inv('sti<i'ati()ns. The i-cstilts of his 

 analyses are shown in the following table : 



Table IV 



Water 



Orj^anic matter 



Inorganic salts 



One hundred parts of the salts contain: 



Chlorine 



SO, 



P260 



K2O 



NaoO 



Calcium phosphate 



Iron pliosphate 



jNIagnesiuni phosphate 



Ca and Mg carbonate and sulpliate 



Silicic acid . 



Chronic 

 phthisis 



!)4.5.-> 

 4.(i7 

 0.78 



35.78 



0.70 



13.05 



24.07 



27.1)0 



1.G3 



0.09 



1.20 



1.74 



0.0 



Acute 

 phthisis 



93.38 

 6.88 

 0.74 



33.40 



0.80 



14.15 



19.99 



31.09 



4.32'- 



0.14 



0.22 



0.3 



PROLIFERATION AND REGENERATION 



The factors that incite cells to proliferate, as well as those that 

 cause the cessation of proliferation after it has once started, are too 

 entirely unknown to permit of speculation as to their exact nature. 

 It seems probable, however, that they are, as Ziegler says, "identical 

 with the stimuli which excite or increase functional and nutritive 

 activity," and these are certainly in many instances of chemical na- 

 ture. Thus the application of various irritating substances in not 

 too concentrated a form (e. g., painting the skin with iodin) may 

 lead to proliferation without causing discernible degeneration of the 

 cells. Mallory's^"' observations on the phenomena of proliferation 

 and phHgocvlT)susjjhowJii^rit the same baj-terial produ cts whicli destr oy 

 the cells when concentrat ed, when su fficiently dilute cause prolif era- 

 tion of similar cells. Carnot and Lalievre "" have obtained evidence 

 that actively growing kidney tissue, whether fetal or adult regener- 

 ating kidney, contains something which is capable of stimulating 

 growth of renal epithelium when injected into other animals. (The 

 importance of this observation calls for its corroboration, but no repe- 

 tition of the work is known to us.) Many other instances of prolifera- 



^•5 Including magnesium. 



98 Jour. Exp. Med., 1900 (5), 15. 



97 Arch. M6d. Exper., 1907 (19), 388. 



