14 PRACTICAL HISTOLOGY [ll 



the coarsely granular cells ; and is round or consists 

 of clumps connected by thin threads in the hyaline 

 cells. 



b. In the red corpuscles the nucleus becomes 

 obvious ; it is when first seen nearly homogeneous, 

 and oval in outline, later it becomes granular and 

 usually irregularly rod-shaped. 



The red corpuscles swell up owing to absorption 

 of water, most after a time become spherical (if strong 

 acid be used the corpuscles usually preserve their 

 shape). 



They become colourless, the hsernoglobin being 

 dissolved from the stroma ; occasionally the haemoglobin 

 is massed round the nucleus before complete solution 

 takes place, and occasionally it stains the nucleus 

 yellow. 



Finally the outline of the corpuscles is seen as a 

 faint line at some distance from the nucleus. Observe 

 the not infrequent excentric position of the nucleus. 



Some corpuscles are much more readily acted on 

 than others. 



6. Irrigate a drop of blood, first with 30 or 50 p.c. alcohol 

 and then with a "5 p.c. solution of Spiller's purple in water or in 

 30 p.c. alcohol. 



The red corpuscle becomes spherical and its peripheral rim, 

 the pseudo-membrane, stains ; the stain is but slight in the 

 corpuscles which have been much exposed to the dilute alcohol. 

 The nuclei both of the red and of the colourless corpuscles stain 

 deeply. 



7. Place several very small drops of blood two or 

 three mm. apart on a slide and leave for a few minutes, 

 then cover with a cover- slip, and put under a high 



