146 DR. E. RLEIN AND PROFESSOR BURDON SANDERSON. 



are situated, ^ve retain the name proposed by Recklinghausen 

 plasmatic canals (juice-canals, Saftcanalchen), but the cells 

 themselves we will call plasmatic canal-cells, lymph-cells or 

 endothelial cells, names the propriety of which Avill be 

 established hereafter. 



The following close relations exist between the endothe- 

 lium of the free surfaces and the plasmatic canal-cells ; 

 some plasmatic canal-cells maybe seen both in the abdominal 

 and the pleural serous surface penetrating between the 

 endothelium with a process, or with a larger or smaller portion 

 of the cell-body which then lies free upon the surface. 

 In the latter case their processes extend between the indi- 

 vidual endothelial cells. Where a plasmatic canal-cell 

 pushes out but one process between two endothelial cells, 

 a smaller area, as seen in silver-preparations, is produced 

 between the areas of the endothelial cells. These spaces we 

 will call pseudo-stomata. 



The lymjohatic system may be injected both in normal and 

 in pathological conditions ; even more easily in the latter 

 provided the alterations have not gone beyond a certain point. 

 The first method we used was that of Ludwig and Schweigger- 

 Seidel, maintaining artificial respiration. Another method, 

 that of Hecklinghausen, consisted in injecting various sub- 

 stances into the abdominal cavity; such as starch emulsion, 

 starch and oil, a solution of alkanin in turpentine, Avhich 

 was divided into minute drops by shaking it up with con- 

 centrated gum solution ; anilin and oil, a mixture in which 

 the oil drops become readily and fully coloured with the pig- 

 ment ; anilin and milk, blood, and a five per cent, solution of 

 Brlicke's Prussian blue. 



The most successful and perfect injection was obtained by 

 keeping a rabbit sixteen or twenty hours without food, and 

 then injecting ten cubic centimetres of the mixture of milk 

 and aniline, or, still better, of the five per cent. Prussian 

 blue solution into the abdominal cavity. After three or four 

 hours the animal was killed by bleeding from the crural 

 artery or was strangled. The whole lymphatic vascular 

 system of the diaphragm then appeared in every case com- 

 pletely injected, as did also the ductus thoracicus, the sternal 

 vessels and the sternal glands. The bronchial glands, on the 

 other hand, were only occasionally and imperfectly injected. 

 Injection seldom succeeds so well with the healthy guinea 

 pig as with the rabbit. The most perfect injection of the 

 centrum tendineum in the latter was obtained in animals 

 affected with artificial tuberculosis (or secondary inflam- 

 mation, Sanderson), Avhich had died in consequence of 



