148 THE BLOOD COKPUSCLES IN ANAEMIA. [BOOK I. 



counted the corpuscles contained in a given volume of blood in three 

 cases of chlorosis, and compared the colouring power of a given 

 volume of the same blood with the colouring power of the same 

 volume of healthy blood. From his observations he concluded that 

 whilst the coloured corpuscles were nearly as numerous in his 

 chlorotic patients as in healthy women, the amount of colouring 

 matter was remarkably diminished, being about three times less in 

 amount. The more recent researches of MM. Hayem 1 and Ma- 

 lassez 2 , but especially of the former, have brought out the interest- 

 ing fact that in the various forms of anaemia the anatomical 

 characters of the red blood-corpuscles are affected, and that the normal 

 relations between the haemoglobin and the other constituents of the 

 corpuscles are disturbed. The following is an epitome of the state- 

 ments of Hayem. 



The changes which occur in the anatomical characters of the 

 coloured corpuscles in anaemia are appreciated if we compare suc- 

 cessively the diseased with the healthy corpuscles ; paying attention 

 to size, number, form and colouration. 



1. Size. In normal human blood we may, according to 

 Hayem, conveniently classify the corpuscles into three orders, accord- 

 ing to size, viz. large, medium, and small ; the large blood-cor- 

 puscles having a mean diameter of 8*5 //., the medium 7'5//,, and the 

 small 6'5/*. Usually the proportions in which these various corpuscles 

 are present is the following: the medium-sized amount to 75, the 

 large to about 12 and the small also to about 12 per 100, so that the 

 mean size of the average blood-corpuscle is (according to Hayem) 7'5/Lt. 



If we except acute cases where the disease is suddenly produced 

 by hemorrhage, in all forms of anaemia the size of the corpuscles 

 is modified. Firstly, the blood contains a certain proportion of 

 unusually small coloured corpuscles, which have a diameter varying 

 between 2 '2//. and 6/i<. Almost as frequently, the blood contains a 

 certain number of unusually large corpuscles, which we may term giant- 

 corpuscles, measuring 10/i,or 12//, or even 14/x. Secondly, the rela- 

 tion between the corpuscles of different sizes is disturbed, so that the 

 blood contains a much larger number of small corpuscles in relation 

 to other sizes than healthy blood. 



In all cases of chronic anaemia of considerable intensity, the mean 

 diameter of the corpuscles is always below the normal. It may fall 

 to 7fj>, to 6'8/ji, to 6'5/z,, and even to 6 ft. 



But this diminution in the mean diameter corresponds to a 

 diminution in the mean volumes of the corpuscles. 



Thus the normal blood-corpuscle, having a mean diameter of 

 7'ojj,, has approximately the volume of 66/^c.c. (cubic micro-milli- 



1 Hayem, Jtecherclies sur VAnatomie normale et pathologique du sang. Avec figures 

 et tableaux. Paris, 1878. Here will be found reprinted the various papers on these 

 subjects, elsewhere published by this author. 



2 Malassez, "Sur les di verses niethodes de dosage de Themoglobine et sur un 

 nouveau colorimetre. " Archives de Physiologic, Ser. n. t Vol. iv. (1877), pp. 143. 



