THE BLOOD AND THE LYMPH. 331 



half of the buffy coat (Remak, Donders). Their less tendency 

 to subside is, moreover, increased by the circumstance, that 

 although they have an uneven surface and a disposition to 

 cohere, they usually do not form any large aggregations and 

 never constitute rouleaux. 



Condition of the blood-corpuscles in various kinds of blood. — 

 However sensitive the blood-cells, out of the body, are towards 

 various reagents, they appear, within it, to be so constant, at 

 all events as regards their shape, that not only within the 

 bounds of the physiological condition, are no notable and uni- 

 form differences to be observed in them, in the arterial and 

 venous blood and the blood of the different organs, but, even 

 in the most various diseases, no visible alterations are pre- 

 sented. And yet it cannot be doubted that, as the colour and 

 chemical composition of the blood-cells vary, so also are their 

 forms subject to certain diversities and changes, according as 

 the blood is more concentrated or diluted, and abounds more 

 or less with one saline constituent or another, or with other 

 substances ; but these changes of form are so inconsiderable, 

 that it cannot be wondered at, that we have not yet been in a 

 condition to recognise them with certainty. At all events, 

 with Henle, I must most expressly declare, that all these 

 forms — the jagged blood-corpuscle on the one side, and the 

 diminutive, spherical, coloured or pale — are never met with in 

 the circulating blood. Slight degrees of flattening and dis- 

 tension may probably be noticed ; but in such researches it 

 should never be forgotten how quickly the blood-corpuscles 

 change their form, and care must be taken not to view a con- 

 dition set up out of the organism, as a natural one. The re- 

 lations of the blood-cells, as to their number, appear to vary 

 more than their forms. As respects the coloured, they are 

 more numerous in the venous than in the arterial blood. In 

 speaking of the venous blood, that of the hepatic veins stands 

 pre-eminent, containing, according to Lehmann, far more blood- 

 cells than that of the portal vein, and even exceeding in 

 that respect the somewhat rich blood of the jugular vein. 

 The colourless blood-cells, as 1 and Funke have found, exist in 

 very great number in the splenic blood, and indeed sometimes 

 more in the form of uninuclear cells, sometimes as multi- 

 nuclear ; and also in the blood of the hepatic veins, according 



