i 2 8 SCIENCE PROGRESS. 



Such a theory is extremely interesting, and no doubt 

 will stimulate fresh work by which the data on which it 

 rests will be thoroughly tested. 1 



I may take this opportunity of alluding" rather more 

 fully to the work of Dr. J. Reynolds Green, who, I learn 

 from a private letter, considers that in my former paper I 

 did not sufficiently emphasise the fact that the credit of the 

 discovery of the importance of calcium salts in coagulation 

 should be shared between himself and Arthus and Pages. 

 It was certainly not my intention to minimise the import- 

 ance of Green's work, but exigencies of space compelled 

 me to allude to it rather briefly. Dr. Green clearly 

 pointed out that calcium salts were necessary for coagula- 

 tion, for if they were removed by dialysis, or by the action 

 of barium chloride, no clotting took place. He, moreover, 

 goes further than Arthus and Pages in considering that 

 the salt of calcium required is the sulphate, for this salt is 

 the most active in setting up the clotting, and fibrin itself 

 contains this substance (Green and Sheridan Lea). 



W. D. Halliburton. 



1 Indeed such work has already commenced. Prof. E. A. Schafer, 

 F.R.S., has communicated to the Physiological Society (Proc. Phys. Soc, 

 March 16, 1895) a preliminary notice of some experiments he has per- 

 formed. He is unable to accept Lilienfeld's distinction between fibrinogen 

 and fibrin, and also doubts Lilienfeld's conclusion that the nucleo-albumin 

 does not enter into the composition of fibrin. 



