CHANGES OF THE BLOOD CORPUSCLES. 1 7 



part in the formation of fibrin during coagulation of the blood ; Eberth and Schimmelbusch 

 ascribe the initial formation of white thrombi to them. According to Lbwit they are formed 

 from partially disintegrated leucocytes, as a consequence of alteration of the blood. Along with 

 the leucocytes they are concerned in the formation of fibrin (Hlava). These structures were 

 known to earlier observers ; but their significance has been variously interpreted. Hayem called 

 them haematobla3ts. Halla found that they increased in pregnancy, Afanassiew in conditions 

 of regeneration of the blood, and Fusari in febrile anaemia ; they are diminished in fever. 



[As to the hsematoblasts, or, as they have also been called, the "globules of Donne" by 

 Pouchet, there seems to be some confusion, for both coloured and colourless granules are 

 described under these names. As Gibson suggests, the former are, perhaps, parts of disintegrated 

 coloured corpuscles, whilst the latter are the blood-plates. The "invisible blood-corpuscles" 

 described by N orris seem to be simply decolorised red corpuscles (Hart, Gibson).] 



IV. Elementary Granules. Blood contains elementary granules (fig. 9, F), 

 [i.e., the elementary particles of Zimmermann and Beale. They are irregular 

 bodies, much smaller than the ordinary corpuscles, and appear to consist of masses 

 of protoplasm detached from the surface of leucocytes, or derived from the dis- 

 integration of these corpuscles, or of the blood-plates. Others, again, are com- 

 pletely spherical granules, either consisting of some proteid substance or fatty in 

 their nature. The protoplasmic and the proteid granules disappear on the addition 

 of acetic acid, while the fatty granules (which are most numerous after a diet rich 

 in fats) dissolve in ether]. 



V. In coagulated blood, delicate threads of fibrin (figs. 9, E, and 12, 6, 7, 8) 

 are seen, more especially after the corpuscles have run into rouleaux. At the 

 nodes of these fibres are found granules which closely resemble those described 

 under III. 



[When the blood-forming process is particularly active, "nucleated coloured corpuscles" 

 or the " corpuscles of Neumann," are sometimes found in the blood. They are identical with 

 the nucleated coloured blood-corpuscles of the foetus, being somewhat larger than the non- 

 nucleated coloured corpuscle ( 7).] . JwiBt , 



10. ABNORMAL CHANGES OF THE BLOOD-CORPCJSCLES. (1) Hemorrhages diminish 

 the number of red corpuscles (at most one-half), and so does menstruation. The loss is partly 

 covered by the absorption of fluid from the tissues. Menstruation shows us that a moderate 

 loss of red corpuscles is replaced within twenty-eight days. "When a large amount of blood is 

 lost, so that all the vital processes are lowered, the time may be extended to live weeks. In 

 acute fevers, as the temperature increases, the number of red corpuscles diminishes, while the 

 white corpuscles increase in number. By greatly cooling peripheral parts of the body, as by 

 keeping the hands in iced water, in some individuals possessing red blood-corpuscles of low 

 resisting power, these corpuscles are dissolved, the blood-plasma is reddened, and even hsemo- 

 globinuria may occur ( 265). 



Diminished production of new red corpuscles causes a decrease, since blood-corpuscles are 

 continually being used up. In chlorotic females there seems to be a congenital weakness in the 

 blood-forming and blood- propelling apparatus, the cause of which is to be sought for in some 

 faulty condition of the mesoblast. In them the heart and the blood-vessels are small, and the 

 absolute number of corpuscles may be diminished one-half, although the relative number may 

 be retained, while in the corpuscles themselves the haemoglobin is diminished almost one- 

 third ; but it rises again after the administration of iron (Hayem). The administration of iron 

 increases the amount of haemoglobin in the blood. [The action of iron in anaemic persons has 

 been known since the time of Sydenham. Hayem also finds in certain forms of anaemia that 

 there is considerable variation in the size of the red corpuscles, and that in chronic anaemia the 

 mean diameter of the corpuscles is always less than normal (7 ju, to 6 fi). There is, moreover, 

 a persistent alteration in the volume, colouring poiver, and consistence of the corpuscles, con- 

 sequently a want of accord between the number of the corpuscles and their colouring power, 

 i.e., the amount of haemoglobin which they contain. In pernicious anaemia, in which the con- 

 tinued decrease in the red corpuscles may ultimately produce death, there is undoubtedly a 

 severe affection of the blood-forming apparatus. The corpuscles assume many abnormal and 

 bizarre forms, often being oval or tailed, irregularly shaped, and sometimes very pale ; while 

 numerous cells containing blood-corpuscles are found in the marrow of bone. In this disease, 

 although the red blood-corpuscles are diminished in number, some may be larger and con- 

 tain more haemoglobin than normal corpuscles. The number of coloured corpuscles is also 

 diminished in chronic poisoning by lead or miasmata, and also by the poison of syphilis. 



(2) The size of the corpuscles varies in disease from 2 '9-12 '9 \x. (mean 6-8 /*) ; "dwarf cor- 

 puscles" or microcytes (6 /t and less) are regarded as young forms, and occur plentifully in 



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