CYSTICERCUS TENUICOLLIS. 181 



the doubtful Helmintha, as by Diesing and Virchow. Rudolphi 

 certainly does not venture to deny its occurrence, but says 

 of it, " res valde ambigua, mihique in cadaverum humanorum 

 aliquot millihus nunquam visa." It is to Eschricht that we are in- 

 debted for having proved that this worm really occurs in the human 

 subject. Eschricht, moreover, thinks that many cystic worms of 

 this species have occurred encysted in the liver of the human sub- 

 ject, and I add to this that they may also probably still remain 

 in museums of pathological anatomy in unopened cysts, having 

 been regarded hitherto, as for instance by Diesing, as Echinococci, 

 or perhaps even as Acephalocysts. Although I have formerly 

 seen in the livers of domestic animals many cysts which simulta- 

 neously harboured Echinococci and Cysticerci tenuicollis } it happened 

 only very recently when I was about giving to a dog a number 

 of cysts cut out of a pig's liver, which had all the same appear- 

 ance, and nearly the same firmness of the walls of the enveloping 

 cyst, were uniformly imbedded in the tissue of the liver, and one of 

 which, when opened and examined with the microscope, was proved 

 to be Echinococcus veterinorum that I nearly allowed myself to be 

 deceived by appearances. And although the pig contained six 

 cysts with Cystic, tenuicollis in the mesentery, I had, nevertheless, 

 from the similarity of their external appearance, regarded the 

 cysts employed in feeding my dog only as Echinococci, and I was, 

 therefore, not a little astonished when a healthy Cysticercus 

 tenuicollis escaped from one of them. In fact, when the envelop- 

 ing cyst is unopened there is sometimes hardly any external dif- 

 ference to be found between Echinococcus and Cystic, tenuicollis, 

 especially when the latter has its habitation in the liver ; and I 

 call the attention of pathological anatomists to this circumstance. 

 We have already seen that a case of Cysticercus tenuicollis must 

 have been referred to by Bonetus and Platerus (' Observ./ lib. 

 iii, p. 635). In the historical portion of his interesting report, 

 Eschricht shows that the case observed by Kolpin, on the mesen- 

 tery of a man, and reported by Bloch, is the first certain case of 

 Cystic, tenuic. hominis. Kolpin himself compared his discovery 

 with the cystic worm figured by Pallas (' Microsc. Zool./ xii), 

 which is a true Cystic, tenuicollis. 



Treutler's case of Cystic, visceralis, which is copied by Jordens, 

 is also deserving of a closer examination, for in this also, accord- 

 ing to Eschricht, a badly reproduced rudiment of Cyst, tenuicollis 

 must be referred to. 



