296 



DISEASES OF THE DIGESTIVE APPARATUS. 



3. The fluke-worms pass directly from the duodenum into the 

 ductus choledochus (Leuckart). This hypothesis has the most 

 probabilities in its favor. According to Leuckart, the progress of 

 the hepatic worms into the liver proceeds as follows : the suction 

 apparatus serves to dilate the narrowest biliary canals ; this alter- 

 nate function of suction produces successively the stretching and 

 contracting of the anterior part of the body, and determines the 

 progress of the parasites, while the scaly appendices of the cuticula 

 prevent its rétrogradation. The lanceolated fluke-worm does not 

 possess any of these points upon the surface of the cuticula, but it& 

 progression is favored by its tenuity. 



If most of the fluke-worms which have invaded the liver remain 

 in the biliary canals, there are some which perforate the walls of 

 these canals, penetrating into the hepatic parenchyma, which they 

 destroy and furrow ; they perforate Glisson's capsule as well as the 

 serous membrane which covers it, and produce a perihepatitis or a 

 peritonitis; others penetrate into the ramifications of the portal 

 system, where the fluke- worms cause endophlebitis, thrombosis, 

 and embolism ; others finally penetrate into the central hepatic 

 veins, and thence to the most distant parts of the body. After 

 having crossed the right heart, the parasites reach the lung, where 

 they produce hemorrhagic centres, also caverns with bloody con- 

 tents and pseudo-tubercles (Gurlt, Rivolta, Hedley, Mégnin, Schell, 

 etc.). It is especially in the ox that cysts and pulmonary tubercles 

 are found, which are of the size of a hazel-nut, a chestnut, or a 

 hen's egg, with thick walls, which are calcified and contain the 

 parasite, swimming in a brownish viscous liquid. Morot has 

 found these parasites in the slaughter-houses of Troy es upon ani- 

 mals of the bovine species, in a proportion of 4 per cent. ; they 

 contained one or two fluke-worms. From these cysts the parasites 

 pass into the pulmonary veins (Friedberger), and are carried along 

 by the strong current of the circulation in the various organs; 

 thus Drosse^ found some in the skin of a cow's belly, and Morro 

 in the intercostal muscles. Hertwig found some in the diaphragm 

 and the pharyngeal muscles of the pig. In man peripheral abscesses 

 with fluke-worms have been found upon the sole of the foot 

 (Giesker), upon the neck (Harris), behind the ear (Fox), and in the 

 region of the right hypochondrium (Dionis). The opinion of 

 Leuckart, according to which the worms would have reached these 



» Drosse: Preuss. Mittheil., 1855-56. 



