Aldred Scott Warthin 77 



blood cells are found scattered throughout the reticulum of the lymph- 

 oid tissue. 



Transition-form? between spleno- and marrowlymph glands are found 

 and also between the latter and ordinary lymphatic glands. The func- 

 tion of the marrowlymph glands is not clear. They are evidently leuko- 

 cyte-forming organs, and the presence of giant-cells and many mono- 

 nuclear eosinophiles suggests the bone-marrow and the formation of 

 red-cells. In certain forms of anemia and leukemia these glands are 

 greatly enlarged and come to resemble the lymphoid marrow, containing 

 nucleated red cells, neutrophile and eosinophile mononuclears, and 

 many giant-cells exactly similar to those of the marrow. It can hardly 

 be doubted that in these cases these glands are centres of red-cell forma- 

 tion perhaps compensatory for the marrow. Under normal conditions 

 they may be in a resting state in so far as their function is concerned. 

 Their part in hemolysis is much less marked than that of the spleno- 

 lymph glands. In old age they become atrophic, their sinuses obliter- 

 ated, large deposits of hyalin occur in them, and finally they cannot 

 be distinguished from atrophic lymphatic glands. The study of these 

 glands from the pathological side promises much more than from the 

 normal. 



SUMMARY. 



Our conceptions of lymphoid tissue are greatly broadened by the 

 study of the hemolymph glands. The intimate relations existing 

 between the different organs of this class, the transition-forms, the 

 possibility of compensation o£ function, etc., throw new and important 

 light upon both histological and pathological problems. The various 

 lymphoid organs might be compared as follows: 



1. LYMPHOID MARROW: 



Hemal gland. 



Blood-forming function. 



Sinusoidal organ. 



Afferent and efferent blood-vessels. 



No afferent lymph-vessels. 



2. HEMOLYMPH GLANDS : 



H«molymph gland. 



Hemolytic function. 



Sinusoidal organ. 



Afferent and efferent blood-vessels. 



No afferent lymph-vessels. 



Efferent lymph-capillaries. 



