302 American Qitartei-ly Alicroscopical Jouniai. 



all red corpuscles alike and give a nucleus to each one. The truth 

 is, a hundred may be examined before finding ten showing " the 

 coagulating effect of the corrosive sublimate." 



This bleaching, hardening and staining method of Bottcher 

 proves the existence of three classes of red corpuscles. 



Those red corpuscles (very few in number) having a nucleus 

 and nucleolus, are recently desired from young white corpuscles. 

 Those having a nucleus only, are either from older white cor- 

 puscles or are the older forms of those red ones possessing a nucleus 

 and nucleolus ; while those consisting of a homogeneous mass are 

 either directly grown from the older white corpuscles, or are the 

 oldest forms of those composing the first or second class. 



The results of Beale's investigations lead to no other conclu- 

 sion, and the recent researches on the structure of the nucleus by 

 Aurbach, Hertwig, Priestley and Klein, do not, in the least, invali- 

 date these statements. 



Although there may be a difference in the structure of the red 

 and white corpuscles, it is only such a difference as the growth 

 of cells renders necessary. 



Some reason must be given for the change in shape from a 

 spherical body to a biconcave disc. 



Haemoglobin possesses a great avidity for oxygen, it also retains 

 this property when united with the white corpuscles, and, under 

 proper conditions, will combine with this gas even in excess. 



Will this excess of oxygen have any effect on the shape of the 

 corpuscle ? 



Using a carbonic acid gas apparatus, of the kind described 

 in the Hand-Book for the PJiys. Lab'y, by Burdon-Sanderson, 

 and examining the blood in a suitable chamber, the effects of the 

 gas on the red corpuscles can be studied. 



It is not to be expected that the carbonic acid will unite with 

 the red corpuscles, but the intention is to displace the excess of 

 oxygen so far as possible, and thus reduce the red corpuscles 

 nearer to the condition of the white. 



Experiments lead to the conclusion that one of the changes re- 

 sulting from this displacement of the excess of oxygen, renders 

 the biconcave red corpuscles more globular. The alteration is 

 not a complete one. The red corpuscle does not become as spher- 

 ical as the white, but such a complete change might be confident- 

 ly expected if all the excess of oxygen could be removed. The 



