202 ANIMAL PARASITES. 



The preceding will be sufficient to incite the pathological 

 anatomists to a fresh and more exact investigation of this cir- 

 cumstance, so as to let us know whether the dead vesicle of an 

 Echinococcus can take on the functions of a true serous mem- 

 brane of the human body and replace it functionally in every 

 particular. In dead EchinocoGci of the liver of the pig I saw 

 the following processes : turbidity of the contents, bloodiness, 

 absorption of the fluid through the walls of the cyst, flaccidity 

 of the walls of the cyst, and conversion of the contents by long 

 absorption into a tough, syrupouj, dingy coloured fluid, but there 

 were no pus-corpuscles. 



If the mother-vesicle of Echinococcus be extracted from its 

 enveloping cyst, we find, between the inner wall of the cyst and 

 the outer wall of the vesicle, plastic exudation, which is thicker 

 in some places than in others. This probably serves both for 

 the enlargement and thickening of the walls of the enveloping 

 cyst, which is strengthened from within outwards, and for the 

 agglutination of the cyst and worm. 



Each individual scolex when alive in its mother-vesicle usually 

 has its head retracted, and only protrudes it after death, when it 

 generally loses its hooks. The scolices, still attached by their 

 stalks to the inner wall of the Echinococcus, may also be brought 

 to protrude their heads when the mother-vesicle is cut open and 

 left for 12 24 hours lying in its fluid. Whilst at first we only 

 find scolices with inverted heads on scraping them off, we now 

 meet with numerous scolices with their heads protruded, and of 

 these the majority still bear the whole or a part of their hooks. 

 The four sucking discs of the scolices are also distinctly seen. 



The experiment of raising Echinococci from the eggs of its 

 mature Tcenia, was made once upon one of the animals already fre- 

 quently mentioned as having been purchased for this purpose at 

 the expense of the Saxon government. Professor Haubner fed a 

 pig with the T. Echinococcus found in Kleinbautzen, and found, on 

 dissecting it several months afterwards, immense numbers of 

 small vesicles, resembling young cystic worms, in the most various 

 organs and parts of the body. Unfortunately none of these 

 vesicles had attained to further development, but we are certainly 

 justified in concluding, per analogiam, that these vesicles were 

 really young Echmococci } which, however, from some unknown 

 reasons, had remained stationary in their development, or had 

 been brought to destruction in consequence of a peculiar indi- 



