184 DR. HENEAGE GIBBBS. 



Lea. This blood supply is very much greater than that of the 

 surrounding alveoli, and appears to be confined to these 

 agglomerations of cells. The capillaries are larger than those 

 of the alveoli, and in an injected specimen mark out these 

 masses of cells very distinctly. 



Another feature is their behaviour to staining reagents. 

 With ordinary logwood solution, the only difference is that the 

 nuclei color very deeply, much more so than the nuclei of the 

 alveolar cells. 



By the use of other staining agents these cell masses can be 

 stained a different colour to the alveoli surrounding them. 



The best stains for this purpose I have found to be vesuvin 

 and sulphindigotate of soda. 



The pancreas should be hardened in chromic acid to get the 

 best results, as after spirit hardening the sections are so 

 delicate they will not stand the different processes. The 

 sections are first placed in a watery solution of vesuvin for ten 

 minutes; a 10-per cent, solution made with distilled water and 

 diluted one half is the best. 



The sections must be well washed in distilled water to get 

 rid of the superfluous colour. They are then placed in a 5-per 

 cent, solution of sulphindigotate of soda until they become a 

 deep blue colour. 



They are then well washed in water and afterwards in spirit, 

 and mounted in Canada balsam. 



It requires some practice to get the right shades of colour, 

 but when this is done the difference between the two tissues is 

 most marked. 



This double stain is also well adapted for other organs. 

 By this method of staining it can be seen that different 

 portions of the pancreas are in different states of activity. A 

 few alveoli will be seen distinctly mapped out from the rest 

 by the way in which their cells have stained , they show the 

 two zones very well. , 



With regard to the significance of these agglomerations of 

 cells, it seems scarcely probable, taking into consideration their 

 distribution amongst so many animals and their distinct blood 



