399 



On the Anatomy of DREPANWoiAEyjA tenuirostris. 



By T. B. Rosseter, F.E.M.S. 

 (Bead October \lth, 1902.) 



Plate 20. 



Rudolphi attributes the discovery of this tape- worm to Bremsery 

 who found it parasitic in the intestine of Mergits serrator Z» 

 (red-breasted merganser) in Vienna, and who placed a type 

 specimen in the museum of that city. Rudolphi also found it 

 parasitic in Mergus cdhellus L. (seamew) at Berlin.* He describes 

 it thus : " Caput subrotundum parvum ; rostellum gracile versus 

 apicem obtusum increscens ; inerme. Collum mediocre." Like 

 Bremser, Rudolphi also placed a type specimen in the Berlin 

 Museum. 



Dujardin, in his '* Histoire Naturelle des Helminthes," 1845,. 

 p. 610, merely quotes Rudolphi in connection with this helminth^ 

 but throws out the suggestion of the possibility of the rostellum of 

 the Bremser-Rudolphi specimen having become deprived of its 

 hooks accidentally. 



Krabbe of Copenhagen examined the specimen which Rudolphi 

 had placed in the Berlin Museum, and describes the w^orm as 

 being 100 mm. long. He also carefully examined the scolex with 

 its rostellum, and discovered that Rudqlphi was in error in saying^ 

 that this was " inerme" as he, Krabbe, found that the rostellum 

 possessed a crown of "10 hooks," the same as his own specimen 

 did which he took from Anas marila in Jutland. Krabbe- 

 figures these hooks together with the rostellum in his work 



* Rudolphi, " Carol. Asm. Entozoorum Synopsis." Berolini, 1819. Tt. 1,. 

 p. 156, sec. 44 ; and pt. 2, p. .509 sec. 44. 



