OEIGIN OF CYSTICA AND CESTOIDEA. f - 75 



rinorum and which did not exceed one, or one and a half lines in 

 length, there was not a single species of Taenice among the many 

 admitted by helminthologists, with which they agreed. I was 

 soon convinced that this small species of tape- worm had been 

 hitherto overlooked by helminthologists ; for it cannot but be 

 admitted that this transformation of the young of the Echino- 

 coccus into sexually-matured Tcenice may take place independently 

 of artificial feeding. In our slaughter-houses, similar scolices 

 must certainly often find an opportunity of entering into the 

 intestinal canal of dogs, the Echinococcus-vesicle, cut out of 

 the viscera of the slaughtered animals and thrown away, being 

 no doubt frequently devoured by the former. It was such a 

 brood of Tania developed from the young of the Echinococcus that 

 Rudolphi probably saw, when he believed that he had discovered 

 in the intestine of a dog, young tape- worms, which were assumed 

 to have been developed by equivocal generation from the villi of 

 the mucous membrane. 1 The little three- jointed tape-worms 

 which Roll twice found in dogs, and which were not long ago 

 described by him as young individuals of Tania serrata, must 

 also of a certainty have owed their origin to scolices of the 

 Echinococcus veterinorum? 



The specific form of the hooks of the circlet of the scolices of 

 the Echinococcus veterinorum, as well as the very small number 

 of Proylottides generated by them, justify me in considering the 

 T(Bni(B developed from these scolices as a distinct species, which I 

 have denominated Taenia echinococcus. (See the ' Zeitschrift 

 fur Wiss. Zool./ B. IV, 1853, p. 423). 



If we sum up the results of these experiments on feeding 

 with Echinococcus veterinorum, they may be shortly stated as 

 follows : 



1. Sexually-developed Tanice have been produced out of all 

 those kinds of scolices known as cystic worms which have been 

 employed for feeding experiments. 



2. From the scolices of the Cysticercus pisiformis } tenuicollis, 

 celluloses, and Ccenurus cerebralis, T&nice of an ell long have 

 been produced, which perfectly agree with both the Tcenia 

 serrata, and with the Taenia solium. 



1 See his ' Entozoorum sive vermium intestinalium historia naturalis,' vol. i, 1808, 

 p. 411. 



2 See Roll's ' Beitrag zur Entwickelungsgeschichte der Taenien,' in theVerhandlungen 

 der Physikal. Medizinischen Gesellschaft in Wiirzburg,' Bd. Hi, 1852, p. 55. 



