98 BLOOD AND LYMPH. 



They have no observable cell-wall, other than some condensa- 

 tion of the peripheral protoplasm. 



The nuclei vary in the different varieties of leukocytes as 

 to number, form, size, and staining properties. The " mono- 

 nuclear" leukocytes contain a single nucleus each. Other 

 varieties when stained appear to contain about three separate 

 rounded nuclei ; but some authorities at present consider that 

 in the living state these nuclei are in most cases connected by 

 strands of the nuclear substance, thus forming a single very 

 irregular nucleus rather than three separate nuclei. The 

 possession by a leukocyte of several distinct (or multiple) 

 nuclei is indicated by the term " polynuclear " ; while the 

 possession of single variable and irregular (or multiform) 

 nuclei is designated by the term " polymorphonuclear." 



Inform the nuclei range from spherical, through horseshoe- 

 shaped forms, to exceedingly irregular and variable coiled and 

 twisted shapes. Their size varies from those that are large 

 and occupy the largest part of the cell to those that are rela- 

 tively smaller. 



The nuclei take nuclear and basic stains with more or less 

 avidity ; the smaller nuclei, in which the chromatin is more 

 concentrated, usually stain intensely ; \vhile the larger nuclei, 

 whose chromatin is more diffused, are less deeply colored. 



The cell-bodies of leukocytes consist of actively vital pro- 

 toplasm. Sometimes, especially during amoeboid movement, 

 two parts can be distinguished in the body-protoplasm, a clear 

 homogeneous hyaline peripheral portion, the hyaloplasm, and 

 a less clear granular portion in the interior of the cell, the 

 granuloplasm. Well-marked granules are present in the 

 bodies of some varieties of leukocytes, absent from others. 

 The granules mostly found are fine neutrophile granules and 

 coarse oxyphile granules (e and granules of Ehrlich's classi- 

 fication) ; fine basophile (8) granules also occur but are incon- 

 spicuous. In the living state the granular appearance of the 

 leukocytes often obscures the nuclei ; but on treatment with 

 acetic acid the granules disappear, the cell-body becomes clear, 

 and the nuclei stand out prominently as about three spherical 

 bodies. 



Varieties of leukocytes : According to variations in size, 

 nuclei, granules, and staining-properties, the leukocytes of 



