662 



APPENDIX. 



of these cells are without nuclei. Occasionally they are found 

 associated with large masses of pus-cells. The epithelium is 

 wanting, and free fat-molecules and globules are abundant. (Fig. 

 370.) 1 



FIG. 370. 



FIG. 371. 



EXAMINATION OF THE GLANDULAR SYSTEM. 



Liver. The relation to each other of the constituent elements of 



the liver, may be easily de- 

 monstrated upon thin sections 

 cut out of the fresh liver of 

 a pig, with a Valentin's 

 knife. The arrangement of 

 the minute vessels are best 

 seen in the injected liver of 

 a frog. The larger vessels 

 can be studied in thin sec- 

 tions, from which the cells 

 have been washed away by a 

 stream of water, and dilute 

 caustic soda afterwards ap- 

 plied. Excellent illustrative 

 specimens of the vessels may 

 be obtained, by injecting the 

 liver of some of the lower 

 animals, as the frog, with two 

 different colors ; throwing one 

 into the portal vein, and the 

 other into the hepatic artery or 

 vein, so that the two shall meet 

 in the capillaries. (Fig. 371.) 

 The hepatic cells lie in the 



1 See a valuable paper by Dr. Da Costa, of Philadelphia, on the Pathological Anatomy 

 of Acute Pneumonia, in Amer. Journ. of Med. Sciences, Oct. 1855. 



Transverse section of a lobule of the human 

 liver, highly magnified, and presenting to view 

 the reticulated structure of the biliary tubes. In 

 the centre of the figure is seen the hepatic vein 

 cut across and several small branches terminat- 

 ing in it. Where the injecting matter did not 

 run freely, it is seen standing in dots along the 

 course of the vessels. At the periphery are 

 seen branches of the hepatic artery, vena por- 

 tarum, and hepatic duct. After Leidy. 



