ECHJNOCOCCUS MULTILOCULARIS 357 



found in all the cysts, and when present only a few, rarely half, of the 

 cysts contain scolices (one or more) ; it is supposed that at least some 

 of these scolices are formed in brood capsules, and that the former 

 are capable of undergoing a cystic metamorphosis. 



One circumstance is peculiar to the multilocular echinococcus 

 of man. namely, the disintegration that sets in at certain stages ; in 

 the centre of the parasite a cavity forms that frequently becomes very 

 large and is filled with a purulent or brownish or brownish-green 

 viscid fluid ; in this fluid one finds shreds of the wall of the cavity, 

 calcareous bodies, echinococcus cysts, also scolices and booklets, as 

 well as fat globules and crystals of haematoidin, margarine and 

 cholesterin and concretions of lime. Such ulcerative processes, 

 according to Ostertag, are never present in the multilocular echino- 

 coccus of oxen, 1 in which the separate cysts are larger and the 

 connective tissue integument less powerfully developed. 



FIG. 259. Echinococcus multilocularis in the liver of the ox. Natural size. 

 (After Ostertag.) 



Hardly anything positive is known with regard to the development 

 of the alveolar echinococcus ; its peculiar conformation is attributed 

 by some to enormous infection of oncospheres, by others to the 

 abnormal situation of one oncosphere ; a few authors ascribe it to 

 infection of lymphatic vessels, others to infection of the biliary ducts 

 or to peculiarities of the surrounding hepatic tissue ; Leuckart ascribes 

 it to a grape-like variety of form which continues budding ; a few 

 more recent authors consider multilocular echinococcus to be specific- 

 ally different from unilocular echinococcus, and therefore also 

 different the species of Taenia arising from them. Melnikow- 

 Raswedenkow is also of this opinion. According to this author the 

 oncospheres infect the lumen of a branch of the portal vein in 



1 This may perhaps be explained by the fact that the hosts are slaughtered before the 

 parasites have attained the size or other conditions necessary to disintegration. 



