202 ELEMENTARY PHYSIOLOGY. [XVIII. 



bundles mark for the most part the course of 

 the lymphatic capillaries of the tendon (cp. 

 §3). 



b. Superficial to the tendon bundles the epithe- 

 lium of the peritoneum consisting of flat 

 polygonal cells. These are larger over the 

 tendinous bundles than over the intervening 

 spaces. Stomata similar to those of § 1 a. /S. 

 may be seen, situated over and communicat- 

 ing with the inter-tendinous spaces. Pseudo- 

 stomata, irregular patches of staining sub- 

 stance at the junctions of the cells, are 

 frequent. 



3. In a guinea-pig or rabbit brush firmly the 

 pleural surface of the diaphragm with a camel- 

 hair brush to remove the surface epithelium and 

 treat with nitrate of silver. Mount in Canada 

 balsam with the pleural surface uppermost. 



a. The small lymphatic vessels, running a little 

 above the tendinous bundles and lined with 

 somewhat irregular spindle-shaped epithe- 

 lium. In places the curved outline of a 

 valve may be seen. 



b. The superficial lymphatic capillaries with 

 their characteristic sinuous epithelium con- 

 tinuous with the lymphatic capillaries of the 

 inter-tendinous spaces. 



c. The origin of the lymphatics. This is best 

 seen in specimens deeply stained with nitrate 

 of silver, so as to produce the so-called 



