TISSUES OF THE BODY. 195 



of the ramifications of the processes may he ohserved, by which the latter 

 become, not unfrequently, membraniform. We likewise ohtain views of 

 isolated, more or less fusiform cells, joining to form fibres, which might be 

 mistaken for elastic were they not acted on by alkalies. Finally, we some- 

 times see and in this the bearing of gelatinous tissue is repeated the 

 cellular network enveloped in thin layers of an intermediate substance, 

 sometimes more or less streaky, and sometimes fibrillated, which may be 

 continuous with ordinary connective-tissue. The matter so deposited is, 

 without doubt, a product of the cells themselves, and may be regarded in 

 the same light possibly as that laid down in cartilage ( 104). 



The mucous membrane of the small intestine supplies a very good 



a- 



Fig. 186. Reticular connective-substance with lymph-cells, from a Peyer's 

 patch of the full-grown rabbit a, capillaries ; 6, reticular sustentacular 

 tissue ; c, lymph-cells. Most of the latter removed by brushing. 



example of the changeable character of reticular connective-substance, 

 as well as its gradual transition into ordinary fibrous tissue. If we 

 examine the tissue, for instance, in the sheep, from the immediate neigh- 

 bourhood of a lymphoid follicle (fig. 187, 1), it still presents its customary 

 reticulated appearance (&), but even at a short distance the banded network 

 may be met with very much thickened and irregular (2). 



Very usually, however, we find, especially around glandular cavities, a 

 more homogeneous and nucleated connective-substance (3, d), which may 

 nevertheless assume the old reticular nature at points (3, b). 



In the .large intestine we find an intermediate form between reticular 

 connective-substance and ordinary fibrous tissue, with a usually small 

 proportion of lymphoid cells. 



We have now to enter on the consideration of the finest and most deli- 

 cate species of this tissue, that of the so-called pulp of the spleen, which 

 takes its rise continuously from the ordinary net-like sustentacular matter 

 of the Mdlpigliian corpuscles of this organ. 



