22 HANDBOOK OF PHYSIOLOGY. 



The buds may be enormously increased both in number and size in cer- 

 tain diseased conditions. 



On those portions of the peritoneum and other serous membranes in 



Fio. 17. Silver-stained preparation of great omentum of dog, which shows, amongst the flat 

 endothelium of the surface, small and large groups of germinating endothelium between which 

 numbers of stomata are to be seen. (Klein.) x 3JO. 



which lymphatics abound (Fig. 18), apertures are found surrounded by 

 small more or less cubical cells. These apertures are called stomata. 



FIG. 18. -Peritoneal surf ace of septum cisternse lymphatic magnae of frog. The stomata, 

 some of which are open, some collapsed, are surrounded by germinating endothelium. (Klein.) 



They are particularly well seen in the anterior wall of the great lymph 

 sac of the frog (Fig. 18), and in the omentum of the rabbit. These are 

 really the open mouths of lymphatic vessels or spaces, and through them 

 lymph-corpuscles, and the serous fluid from the serous cavity, pass into 



