414 HISTORICAL ACCOUNT OF T^NIA SAGINATA. 



who had no opportunity of observing any other tape-worm than 

 Bothriocephalus, and who believed that there was no other species in 

 Geneva, had, when examining his Tcenia saginata, only found a com- 

 paratively short chain of joints at his disposal, and the shortness of 

 the anterior joints, which is so characteristic of this species, would all 

 the more easily lead him astray, since he was inclined to base his 

 specific distinctions principally upon the form of the joints, as may 

 be seen from the fact that he named the modern Bothriocephalus (re- 

 garded by him as the Lumbricus latus of the ancients) " Tcenia a 

 anneaux courts," in contradistinction to Tcenia, which he calls " Tcenia 

 a anneaux longs." 



Although Bonnet himself recognised his mistake, 1 and exposed 

 the delusion under which he had been labouring, by discovering the real 

 head of his Tcenia lata (Bothriocephalus), and demonstrating its wholly 

 different structure, yet the false idea which he originated has been 

 of most fatal influence in the history of Tcenia saginata. 



Bonnet's second work was less circulated, and the corrections 

 were almost completely overlooked, and thus it happened that a worm 

 called Tcenia lata was known in helminthological literature until the 

 time of Bremser (1819), who appreciated 2 Bonnet's later observations, 

 and also recognised a species of Eudolphi's genus Bothriocephalus in 

 Bonnet's worm. This so-called Tcenia lata was said to be charac- 

 terised by short joints, a median generative opening and coiled 

 uterus (d corps en manibre de fleurs), associated with a hookless head 

 with four suctorial pits a species, indeed, which does not occur at all 

 in nature. 3 



Nor was it only a few or the more inexperienced who adhered to 

 this error, but the greatest helminthologists of the time, headed by 

 Pallas, 4 and including Goze, 6 Bloch, 8 and Eudolphi. 7 None of them 

 had any hesitation in recognising Tcenia lata as a fully justified species, 

 without, however, being able in any way to confirm Bonnet's state- 

 ments on the ground of their own investigations. 



1 " Nouvelles recherches sur la structure du Teenia," Observed, sur la Physique, <kc., 

 p. 243, Paris, 1777. 



2 " Lebende Wiiriner," &c., p. 92. 



3 That the real Tcenia saginata is sometimes designated by the name Tcenia lata, in- 

 stead of this fictitious animal, is shown by the fact that in the Giessen Zoological Museum, 

 lately incorporated with v. Sominering's collection of Helminths, there was a T. saginata, 

 to which this name was affixed, while the Tcenice (with hooks) were correctly named T. 

 solium. 



4 "Bemerkungen iiber die Bandwurmer in Menschen und Thieren," Neue nordische 

 Beitrage, i., p. 64, 1781. 



6 " Versuch einer Naturgesh.," &c., p. 298, 1782. 



6 " Abhandlung von der Erzeugung der Eingeweidewiirmer," p. 17 : Berlin, 1782. 



7 " Entozoor. hist, natur.," vol. ii., p. 70, 1810. 



