ON THE PHAGOOYTES OF THE ALIMENTARY CANAL. 495 
cellular digestion is probably true for them also (see figs. 10, e; 
12, f; 1S5 pe 
The intracellular destruction and digestion of micro- 
organisms taking place in the interior of the Peyer’s patches 
remain to be described. Few micro-organisms only are seen 
in the tissues near the epithelial border, or in the upper and 
middle layersof the patch. The deep, though not the deepest 
parts of the patch, contain the largest number of them, and 
in the rabbit they are found there in almost incredible numbers; 
150, 200 or more in one field of the microscope (Vérick, oc. 3, 
obj. immers. ;4,). Careful staining reveals the fact that all 
the micro-organisms are in the interior of the cells, and never 
lying free between the cells; never in the vessels or in the 
submucous muscular and peritoneal coats, or even in the 
deepest layers of the lymphoid tissue. The lymphoid tissue 
might be compared toa filter, or more aptly to a battle-ground 
for cells and micro-organisms; the former always proving 
victorious in healthy animals. 
Some of the micro-organisms found within the cells react 
normally to the colouring matter (see fig. 8, a, b, c) (Weigert’s 
method), but others show the following changes. Some stain 
of a paler colour, but uniformly (fig. 15, a, 3), whilst others 
do not retain the colouring matter at all in the centre, though 
the peripheral parts still react normally staining to reagents 
(fig. 15, y, 6). Others present a mottled appearance (fig. 9, a), 
whilst others, again, resemble strings of micrococci as their 
different parts take up the gentian-violet unequally. Some 
bacilli deeply stained at each end show acentral part which is 
quite pale and almost colourless (fig. 10, a). Others, again, 
are irregular in shape (figs. 15, 6, 14, a). It is quite possible 
that the mode of decolouration varies according to the kind of 
micro-organisms, to their vitality, or according to the digestive 
power of the micro- or macro-phage containing them. 
In a more advanced stage of degeneneration the micro- 
organisms lose their power of absorbing and retaining aniline 
dyes, but take up alum-carmine or logwood instead. Some of 
them are then of a pale-red or even deep-red colour (figs. 8, 6, 
