jq5 HOWELL. [Vol. IV. 



consequence of the time which elapsed before getting the slip 

 into Hayem's liquid. The method also gave beautiful per- 

 manent specimens of fibrin reticulum and of red corpuscles, 

 which retained their normal shape and stained deeply with 

 eosin. The negative result of this experiment, together with 

 certain other facts which will be given later in speaking of the 

 blood plates, convinced me that there is no connection between 

 the blood plates and the nuclei of the mature nucleated red 

 corpuscles. There remains, then, only the theory that the 

 liberated nuclei are dissolved in the blood plasma, and go to 

 form in all probability one of the proteids of the blood. 



It is, perhaps, unwise to speculate further upon the fate of 

 the dissolved nucleus without some experimental basis to reason 

 upon. However, my idea is that the free nuclei are dissolved 

 in the blood plasma while still in the blood-forming organ. I 

 have seen appearances in the marrow in sections which may 

 represent this process of dissolution ; that is, one meets occa- 

 sionally with what seem to be globules of varying size from 

 tiny drops to spheres larger than a white corpuscle which, like 

 the free nuclei, stain deeply with saffranin, though of a different 

 tint. Usually these are found in clusters of different sizes, 

 and possibly they represent the free nuclei, undergoing 

 changes preparatory to solution, though I have not found in- 

 termediate stages. These globules are evidently not a fat of 

 any sort, as one might suppose from their general appearance, 

 since otherwise they would have been dissolved during the 

 process of imbedding. With reference to the material produced 

 by the nuclei after solution, there seemed to me certain reasons 

 for believing that the fibrinogen of the plasma is the product 

 formed. Influenced chiefly by this idea, I asked Mr. Dreyer 

 of the Johns Hopkins University, and formerly assistant in 

 physiology, to investigate the changes in the blood plasma 

 caused by severe bleeding. His results, which are very inter- 

 esting in a number of ways, have not yet been published. It 

 may be said, however, that with reference to the fibrinogen, 

 he found that its percentage in the plasma was always increased, 

 sometimes nearly as much as lOO per cent., over what it had been 

 in the same animal before bleeding, the analysis in all cases 

 having been made twenty-four hours after the bleeding. This 

 striking increase in the fibrinogen is more remarkable because 



