446 



Since the discovery of epithelium upon mucous membranes, 

 the same thing has been found upon serous and synovial 

 membranes, which are supposed now to be only peculiar 

 modifications of the former ; the layer is a single one, and is 

 best seen in the mesentery of small animals, and In the 

 synovial fringes of joints. These synovial fringes, when 

 injected, are remarkably beautiful objects; by some persons 

 they have been looked on as small masses of fat, but on 

 microscopic examination, the notion of their being of a 

 glandular nature, as was described by some of the older 

 anatomists, wIU be found to be correct. To examine the 

 epithelium from these parts, the mesentery of a small animal, 

 such as a jnouse, guinea-pig, or rabbit, should be taken as 

 soon after death as possible ; the epithelium may be best seen 

 on the parts that are slightly folded, with a power of two 

 hundred diameters. 



In addition to the membranes last described, the arrange- 

 ment of the capUlaries in certain of the elementary tissues 

 win also form very beautiful objects for examination. The 

 following is a list of the most Important : — 



Areolar Tissue, Human, Areolar Tissue, Fowl, 



Horse, Ostrich, 



Rat, Frog, 



