HANDBOOK OF PHYSIOLOGY. 



sac of the frog (fig. 22), and in the omentum of the rabbit. These are 

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



Fig 23. A portion of the great omentum of dog, which shows, among the flat endothelium ol 

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

 X 300. 



them lymph-corpuscles and the serous fluid from the serous cavity past 

 into the lymphatic system. They should be distinguished from srnallei 

 and more numerous apertures between the cells which are not lined bj 



Fig. 



Fig. 25. 



Fig. 24. A small piece of the liver of the horse. (Cadiat. ) 



Fig. 25. Glandular epithelium. Small lobule of a mucous gland of the tongue, showing nu- 

 cleated glandular cells, x 200. (V. D. Harris.) 



small cells, although the surrounding cells seem to radiate from them, 

 filled up by intercellular substance or by processes of the cells under- 

 neath. These are called pseudo-stomata (fig. 23). 



