T. B. ROSSETER ON EXPERIMENTAL INFECTION OF DUCKS. 405 



Should an epizobty of these entozoons occur in our poultry- 

 yards — which is by no means improbable, more especially as 

 regards the Anserictae and Anatinidse — we now know authorita- 

 tively, by experiment and demonstration, the source of the 

 infection ; and measures could easily be devised to arrest the 

 spread of the disease, a disease which has played sad havoc at 

 different periods amongst the flocks of breeders of poultry on the 

 Continent of Europe. 



Addendum. — I had hoped to have added Cysticercus sinuosa to 

 this list, as I am feeding this Cysticercus to ducks so as to 

 produce Dreimnidotcenia sinuosa; but my experimental infesta- 

 tions are not yet sufficiently matured. 



Reference to Figs, on Plate XVIII. 



Fig. 1. Dicranotcenia coronula x 28. 



2. Hook from rostellum x 900. 



3. Cysticercus coronula x 140. 



4. Hook from embryonic rostellum x 900. 



5. Drepanidotcenia gracilis X 140. 



6. Hook from rostellum x 340. 



7. Cysticercus gracilis x 140. 



8. Hook from embryonic rostellum X 340. 



9. Drepanidotcenia tenuirostris with rostellum everted 

 x 62. 



10. Same with rostellum inverted x 62. 



11. Rostrum of Drepanidotwnia tenuirostris x 230. 



12. Hook from same x 930. 



13. Cysticercus tenuirostris x 140. 



14. Hook from embryonic rostellum x 930. 



