ECHINOCOCCUS MULTILOCULARIS 259 



tive processes, according to Ostertag, are never present in the 

 multilocular echinococcus of oxen, 1 in which the separate cysts are 

 larger and the connective tissue integument less powerfully developed. 

 Hardly anything positive is known with regard to the develop- 

 ment of the alveolar echinococcus ; its peculiar conformation is 

 attributed by some to enormous agglomerations of oncospheres, by 

 others to the abnormal situation of one oncosphere ; a few 

 authors ascribe it to agglomerations in lymphatic vessels, others 

 to agglomerations in 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 specifically different 

 from unilocular echinococcus, and therefore also different the 

 species of tsenia arising from them. Melnikow-Raswedenkow is also 

 of this opinion. According to this author the oncospheres settle 

 in the lumen of a branch of the portal vein in Glisson's capsule 

 of the liver and grow into an irregularly-shaped formation (chitinous 

 convolution), which breaks through the vascular* walls and thus 

 forms the alveola. So far the views coincide well with Leuckart's 

 opinion of the original grape-like form of the Echinococcus nmlti- 

 locularis ; according to Melnikow-Raswedenkow the " granular 

 protoplasmatic substance " (parenchymatous layer) is not only 

 present in the interior of the loculi but also outside, and, moreover, 

 " ovoid embryos " are supposed to develop in the chitinous con- 

 volutions, which, " thanks to their amoeboid movements, reach the 

 lumen of a vessel, where, under favourable circumstances, they 

 begin to develop further," that is to say, they become " chitinous 

 cysts with fantastic outlines," or also " single-chambered chitinous 

 cysts " ; scolices may develop in both. 



The multicular echinococcus, which in man produces a severe disease 

 and almost always leads to premature death, settles most frequently in 

 the liver, but may also be found primarily in the brain, the spleen and 

 the supra-renal capsule ; by means of metastasis it may reach the most 

 various organs from the liver, especially those of the abdomen, but also 

 the lungs, the heart, &c. Hitherto 235 cases have been described, being 

 70 from Russia, 56 from Bavaria, 32 from Switzerland, 30 from the 

 Austrian Alps, 25 from Wiirtemburg ; the remaining cases are distributed 

 over Central Germany, Baden, Alsace, France, Upper Italy, North America ; 

 in some the origin is doubtful ; in any case after Russia, the mountainous 

 South of Europe is the principal region of distribution. As to the domesticated 



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. 



