No. I.] BLOOD CORPUSCLES. 



Fate of the Extruded Nucleus. 



105 



If the nucleus of the nucleated red corpuscle is extruded, 

 the next point to be determined is what becomes of it. Naked 

 nuclei, similar in all respects to the nuclei of the mature nu- 

 cleated red corpuscles, can be found easily in the marrow, where, 

 indeed, several observers have called attention to them, and 

 also in the foetal liver at the time of its haematopoietic activity, 

 where they have been noticed before by one writer, at least, — 

 Neuman {<)d), — who has described them very carefully and 

 attributed to them some function in connection with the 

 production of new corpuscles. It is fair to assume that the 

 free nuclei are turned out into the blood stream alono; with 

 the new red corpuscles. In that case, one of two fates awaits 

 them. Either they persist as a morphological element of the 

 blood, or they are dissolved in the blood plasma. Upon the first 

 hypothesis, we can only suppose that the free nuclei become 

 the blood plates, as no other element of the blood resembles 

 them in size or structure. This theory has, in fact, been pro- 

 posed by Gibson, though as far as I can see, he gives no proofs 

 in its favor. I was also at first impressed with this idea ; but 

 the only experiment which suggested itself to me to test the 

 hypothesis gave me unfavorable results. The nuclei of ma- 

 ture nucleated red corpuscles, when treated with the triple 

 stain of hosmatoxylin, eosin, and saffranin, show a preference 

 for the saffranin, while other nuclei take the haematoxylin. 

 If the blood plates are derived from these nuclei, they ought 

 to show something of the same behavior toward the triple 

 stain. On the contrary, specimens of blood plates treated 

 with the triple stain always take the haematoxylin, though they 

 do not stain deeply. The method of preparing and staining 

 the blood plates was as follows. A drop of blood was placed 

 upon a slide, a cover slip was dropped upon it, and moved 

 round once or twice. The slip was then taken off, and by this 

 time a number of blood plates had adhered to its under side. 

 It was next immersed in Hayem's liquid, to fix the blood plates 

 and wash off the excess of blood plasma, and was then hard- 

 ened like a piece of marrow in mercuric chloride, followed by 

 alcohol, and afterwards stained. I obtained in this way good 

 specimens of blood plates, somewhat deformed, of course, in 



