No. I.] BLOOD CORPUSCLES. lOi 



make the corpuscle rotate in the liquid, I found no exceptions 

 to this position of the fragment. A remarkable thing about 

 the phenomenon was its persistence. Even two weeks after 

 bleeding, a drop of the blood taken from the ear showed a 

 number of these corpuscles. I was successful afterwards in 

 getting the same result from other cats, though I had many- 

 failures. The necessary condition seems to be that the ani- 

 mal should be bled quickly and severely. At first, I supposed 

 that the objects in question were simply large granules floating 

 in the blood which had adhered to the corpuscles ; but I was 

 soon convinced that this was not the case. The frasfments 

 could not be detached from the corpuscles either by shaking 

 or by the addition of water, acetic acid, and other reagents, 

 which dissolve out the haemoglobin from the corpuscles. More- 

 over, a number of corpuscles were without the fragments, and 

 in normal cats no such appearance could be obtained. The 

 only satisfactory explanation of the phenomenon which has 

 occurred to me is that the fragment is a bit of the nucleus 

 left adhering to the corpuscle at the time that the nucleus 

 escaped. Under the conditions necessary for the appearance 

 of the phenomenon, we may suppose that the process of pro- 

 duction of new red corpuscles was vastly accelerated, and that 

 therefore the extrusion of the nucleus was not as perfect as 

 under normal conditions. The portion remaining in the cor- 

 puscle is not absorbed at all, but probably remains with the 

 corpuscle up to the time of its dissolution. Whether or not 

 my view as to the origin of the fragment is correct, there 

 can be no doubt that it is not absorbed in the corpuscle 

 while in the blood, but remains with it up to the time of its 

 destruction. At the suggestion of Dr. Bowditch, I had hoped 

 to use the phenomenon to measure the average length of life 

 of the red corpuscle of circulating blood, but have hitherto met 

 with certain difificulties which I hope soon to overcome. 



After I was convinced from a study of teased specimens and 

 sections that the nucleated red corpuscle loses its nucleus by 

 extrusion, it seemed to me that it might be possible to watch 

 the process taking place in the living cell. The experiments 

 that I made for this purpose were not very numerous, for 

 reasons that will be given below ; but they were successful in 

 a measure, at least. The method employed was to use the 



