HISTORY OF CYSTICERCUS TENUICOLLIS. 565 



long. Yet there are but few hints of such knowledge, with the ex- 

 ception of Hartmann, who (in 1685) made his discovery of the animal 

 nature of the bladder- worm in connection with this very form. It is, 

 however, possible that the size and occurrence of this worm have led 

 to its being confused and ranked with Echinococcus. This has been a 

 serious source of error, even as regards its human pathology. On the 

 strength of certain cases, partly chronicled by Bonetus and partly the 

 subject of later observation, Cysticercus tenuicollis has often been 

 reckoned among the human parasites, especially under the title C. 

 visceralis. We must also concede that many of these cases admit 

 of such a construction, as those of Plater 1 and Koplin, 2 where re- 

 ference is expressly made to C. tenuicollis. The identity is never, 

 indeed, certain, so that the occurrence of the latter in man was re- 

 garded as a debateable point, as Eudolphi concludes, from the negative 

 results of over a thousand post mortem examinations. About twenty- 

 live years ago, however, it became apparently certain that Cysticercus 

 tenuicollis, which had meanwhile been observed in monkeys, was also 

 occasionally found in the viscera of man. This was the result of the 

 researches of Eschricht 3 regarding a number of bladder-worms which 

 were collected by the well-known Dr. Schleisner in his observations 

 on the Icelandic liver disease. Among these objects Eschricht 

 found, besides several Echinococci, also a Cysticercus tenuicollis. There 

 is no question as to the reality of this, but in consequence of Krabbe's 

 results, we are forced to the conviction that there was some confusion 

 or mistake in the sending of the worm in question. 4 In point of 

 fact, the C. tenuicollis has never been found in man by the Icelandic 

 physicians, 5 although the T. marginata is everywhere the most 

 frequent tape-worm in the dog, and an infection with its eggs could 

 hardly be any more difficult than with those of T. echinococcus. 



Such being the case, and knowing that T. marginata never 

 develops as a tape- worm in man, as has been proved by the experi- 

 ments made on himself by Dr. Moller in Altona, 6 we might then 

 leave it out of account, were it not that the worm in its Cysticercoid 

 stage is of great interest both to pathologist and zoologist, and affords 



1 Bonetus, " Sepulchretum," Obs. Lib. iii., p. 635. 



2 Schriften d. Gesellsch. naturf. Preunde, i., p. 350. 



3 " Undersogelser over den i Island endeiniske Hydatidensygdom," Danske Vidensk. 

 Selsk. Forhandl, p. 211, 1853. 



" Rech. helmintholog. en Danemark et en Islande," p. 43 : Copenhagen, 186G. 



6 Von Siebold thinks that the liver disease of the Icelanders must be wholly referred 

 to the parasitism of Cysticercus tenuicollis (" Band- und Blasenwurmer," p. 113). This 

 statement, however, is erroneous ; for even Eschricht, to whom v. Siebold refers, only 

 knew the one case above recorded, and rightly sought the cause of the disease in the 

 Echinococcus. 



6 Kuchenmeister, loc. cit., p. 319, note. 



