634 OCCURRENCE AND MEDICAL IMPORTANCE. 



designated the above-cited case as exhibiting " countless JSchinococci" 

 but in point of fact they are reduced apart from the secondary 

 hydatids of course to less than a hundred. It seems to me also that 

 the <; thousands " spoken of by Kuchenmeister in the last edition of 

 his work on parasites are the result of a similar excessive estimate. 1 



But even if the number should not be much over a hundred, it is 

 large enough to suggest the question whether we have here the result 

 of a single infection. 



When we consider that the multiple Echinococci exhibit usually 

 very considerable variations in the size and development of the 

 bladders, we are inclined at first to suppose that a repeated importation 

 of the Echinococcics-\)Tood. has occurred. The above-mentioned dis- 

 parities would then be readily explained by a supposition not in 

 itself improbable. Nevertheless I believe that a repeated infection 

 with the Echinococcm-brood must be very rare, for even a single 

 infection demands the co-operation of manifold factors. In certain 

 cases of Cysticercus celluloses we might admit the supposition without 

 difficulty, but here the conditions are essentially different, since the 

 Tcenia solium, which furnishes the material for infection, is much 

 nearer to man than the T. cchinococcus, whose eggs only reach us from 

 the dog. 2 



If, then, the multiple Echinococci are to be referred to a single 

 infection, it does not follow with absolute certainty that they are all 

 of the same age. The .^cAmococms-bladders have, as we know, the 

 power of proliferation, and even of manifold proliferation ; it is 

 therefore possible than in the multiple Echinococci, in addition to the 

 first immigrants, we have their descendants. 



We think first of the possibility of an exogenous proliferation a 

 process which does indeed come into consideration in explaining the 

 multiple Echinococci. But this supposition is only admissible when 

 the bladders, large and small, lie close beside one another, or at short 

 intervals. But, as a rule, the multiple Echinococci are scattered over 

 different, often widely separated organs, so that this explanation is 

 insufficient. For such cases one must refer to the observations of 

 Naunyn and Rasmussen, who have shown that heads and brood- 



1 In the description of one of the two cases observed by Kuchenmeister we read as 

 follows (loc. cit. t p. 214) : "All the organs of the pelvic cavity were filled with 

 Echinococcus-bl&dders from the size of a hazel nut or walnut to that of an apple or a fist. 

 There must have been towards a thousand." No enumeration, however, is made, and the 

 approximate estimate cannot be right, since 1000 bladders, even of the size of a walnut, 

 would fill about a cubic foot, more than the whole contents of the pelvic cavity. Even the 

 "many hundreds," to which Kuchenmeister has now reduced them, must surely be still 

 too high an estimate. 



a I repeat that Kiichenmeister's supposition of the occurrence of Tcenia echinococcus in 

 man (and also in the pig, the ox, the sheep) is quite baseless. 



