50 NORMAL HISTOLOGY. 



mosaic of endothelial cells. The outlines of these cells 

 on both sides may be brought successively into view by 

 careful focussing. 



Endothelium of the Omentum. A portion of the omen- 

 turn of the dog should be treated with silver in the way 

 just directed for the mesentery, and also stained with 

 haematoxylin and mounted in glycerin. The omentuni 

 of the dog, as of man, consists of an irregular-meshed 

 net, whose trabeculse are made up of fascicles of fibrillar 

 connective tissue of varying thickness, the broader con- 

 taining blood- and lymph-vessels and fat-cells, the nar- 

 rower consisting of single bundles of fibrillse all being 

 alike covered with a single layer of endothelium. In 

 many parts the endothelial cells are seen in profile, when 

 their nuclei appear lenticular in form, usually projecting 

 above the general level of the cell-body, which is itself 

 in most cases thicker in the vicinity of the nucleus than 

 at the points of junction with adjoining cells. The 

 specimens of both omentum and mesentery may be pre- 

 served in the usual way ; but silver preparations, like the 

 gold, do not preserve their first clearness very long, 

 unless carefully kept from the light. 



