STRUCTURE AND DEVELOPMENT OF ECH1NOCOCCUS 



255 



The echinococcus fluid, which originally is formed from the blood of 

 the host, is light yellow, with a neutral or slightly acid reaction ; its 

 specific gravity averages 10,09 to 10,15. It contains about 1-5 per cent, 

 of inorganic salts, half of which is common salt ; in addition (besides water) 

 it contains sugar, inosite, leucine, tyrosin, succinic acid (associated with 

 lime or soda) and albumens which are not coagulated by warmth ; occa- 

 sionally also the fluid has been found to contain haematoidine and uric acid 

 salts (in echinococcus of the kidneys), which doubtless demonstrates that the 

 echinococcus liquid originates from the host ; finally, there is present a 

 substance with toxic properties (leucomaine) which, if introduced into the 

 abdominal cavity, causes peritonitis, which, as a rule, has a fatal termination. 1 



According to the researches of Leuckart, the growth of the 

 echinococcus is very slow ; four weeks after infection the 

 average size is only 0-25 035 mm., at the age of eight weeks it 

 is i 2'5 mm., and at this period the formation of the central 

 cavity commences ; at the age of five months and with a size 

 of 15 20 mm. the first brood capsules with scolices are formed. 

 The consequence of this gradual increase of size is that the 

 organ attacked can maintain its functions by vicarious hypertrophy, 

 and that many echinococci induce no special symptoms and cannot 

 even be diagnosed, the latter circumstance being due to their hidden 

 position. 



The Echinococcus cannot be said to be scarce in man, as is 

 shown by the following table for Central Europe : 



These, however, are only cases that have become known by 

 post mortem ; in addition there are cases that have been treated 

 medically, of which there are a few statements, at all events 



1 Drago, U., Ric. sull' azione di ale. lig. idatid. e significato biol. dci mcdesmi 

 Rassegna internaz. d. Med. mod., 1900, i., No. 16, and other authors. 



