SPLEEN. 



141 



called histological units (Mall). These units are, however, in 

 communication with one another. The terminal arteries run 

 into these units and end in the ampullce of Thoma, a small 



FIG. 99. 



Diagram of the lobule of the spleen. (Mall.) A, artery in the ceutre of the lobule; 

 V, interlobular vein within the interlobular trabeculge ; TV., intralobular trabeclse ; L, Mal- 

 pighian follicle; (7, iutralobular collecting vein; P, intralobular vein plexus which sur- 

 rounds the pulp cords or histological units ; Am, ampulla of Thorna. 



dilatation. There is evidence to show that these ampullae 

 communicate both with one another and with the terminal 

 veins. 



According to some authors, the capillaries open directly 

 into the veins, while others have described a system of lacunae 

 between them. This is known as the intermediary path for 

 the blood. The capillaries show a funnel- like widening as they 

 pass over into the veins (Plate VI., Fig. 100). This interme- 



