ANIMAL PAEASITES. 19 



the observation of the intestinal worms in general. But the 

 most powerful stimulus to the development of helminthology in 

 general, and for some time to that of the theory of the cystic 

 worms, was given to science by the proposition, in the year 1780, 

 on the part of the Academy of Sciences of Copenhagen, of the 

 following prize essay : " Ueber die Samen der Eingeweide- 

 wiirmer ; ob die Tsenien u. s. w. den Thieren angeboren sind, 

 oder ob sie von aussen in sie kommen. Diess ist mit Erfahr- 

 ungen und Griinden zu beweisen, und es sind Mittel gegen sie 

 vorzuschlagen." In his prize memoir, ' Abhandlung von der 

 Erzeugung der Eingeweidewurmer/ Berlin, 1782, Bloch esta- 

 blished a peculiar genus, " Vermis vesicular is," which rather 

 approached the Echinorhynchi than the Taeniae, but Bloch's work 

 did no other essential service to the elaboration of our problem. 

 For the most important contribution to this object we are in- 

 debted to Goeze, although the observations scattered through his 

 works have remained up to our own day neglected and even mis- 

 understood. Goeze, although he still believed in the zoological 

 independence of the cystic worms, nevertheless reckoned them 

 amongst the Taeniae, distinguished them as T, viscerales from the 

 intestinal tape-worms, T. intestinales and referred to several 

 species of his T. vesiculares hydatigenae (Cysticercus, Zeder; Vesi- 

 caria, Schrank ; Hydatula, Abilgaard), such as T. hydatig. orbi- 

 cularis (Cystic, tenuicollis, Rud.), T. hydatig. pisiformis and 

 utriculenta (both probably C. pisiformis), T. hydat. fasciolaris 

 (C. fasciolaris, Rud.), T. hydat. vesical, multiceps, from the brain 

 of the sheep (Ccenurus cerebralis, Rud.), and T. visceralis socialis 

 granulosa (Echinococcus, Rud.) He was thoroughly aware of the 

 similarity of the heads of the cystic worms and Taenia, which 

 he was the first to discover with regard to Echinococcus, and like 

 Pallas he recognised the perfect similarity of the head of T. 

 crassicollis (his T. serrata of the cat) with that of Cysticercus 

 fasciolaris. This appears most distinctly from a passage in his 

 ' Versuch einer Naturgeschichte der Eingeweidewiirmer/ 1782, to 

 which Eschricht first called attention. At page 340 of this work, 

 he says, " The size, form, and structure of its head are perfectly 

 identical with those of the head of the articulated cystic tape- 

 worm in the liver of the mouse ; for this also has no neck, 

 but its head sits immediately upon the first segment. But who 

 can say Avhy these two species are so similar as regards the head, 

 and so heterogeneous in the rest of their economy? — and also, 

 at p. 222, in the description of his " large-headed, band- 



