SUPPURATION. lia 



and the nuclear structures start into clear relief. There is 

 usually more than one nucleus ; often three or four. In the 

 latter case, the nuclei are small, not always strictly circular, and 

 exhibit a peculiar lustre which suggests the homogeneity of their 

 structure (fig. 38). These cejls were at one time considered to 

 be of specific nature, and were hence termed pus-corpuscles. 

 This was an error ; for we meet with similar cells in the blood, 

 where a certain number of the colourless corpuscles are multi- 

 nuclear ; and with regard to these, Vircliow declares that they 

 are incapable of taking any farther part in the deyelopment of 

 the blood. More recently it has been shown that saturation of 

 the blood with carbon dioxide causes all the uninuclear colour- 

 less cells to become multinuclear and then to undergo disin 

 tegration. The presence of seyeral nuclei has not the same 

 significance here, as that diyision of the nucleus which precedes 

 the fissiparous multiplication of cells ; it seems rather to point 

 to a breaking-up of the cell, preliminary to its total dissolution. 

 Moreoyer, it is a mistake to suppose that pus contains only cells 

 of this kind. Creamy pus indeed {pus honum et laudahile), such 

 as is poured out on surfaces clothed with healthy granulations, 

 contains a large majority of uninuclear cells, which I should not 

 be able to distinguish from the migratory corpuscles of connec- 

 tlye tissue. Sanious pus, on the other hand, such as is yielded 

 by carious bone, contains, as a rule, cell-deriyatives, oil-globules, 

 albuminous molecules, &c., rather than pus-cells. In fact, 

 we find a series of transitional forms between the uninuclear 

 and the multinuclear elements of pus, just as in the case of 

 white blood- corpuscles ; the latter, incapable of further develop- 

 ment, undergoing disintegration by fatty and granular meta- 

 morphosis. According then as the pus is fresh or stale, 

 according as it has been rapidly or slowly produced, or has 

 undergone a slower or more rapid decomposition, do we find in 

 it uninuclear or multinuclear cells or even cell-debris. 



§ 95. When we hear it asserted that pus may be produced 

 in various ways, when we find pus-formation in connective 

 tissue, such as we have just now been considering, contrasted 

 with pus-formation on mucous and serous surfaces, or in coagu- 

 lated blood, &c., we must, in the present state of our know- 

 ledge, accept such contrasts with a grain of salt. The great 

 bulk of pus is everywhere formed by the migration of colourless 



