505 



Dujardin (1845, pp. 574-575, T. rhombuidea) found a 30mm 

 frag-ment and 6 young worms ]omin to 18mm long in a wild duck, 

 in which 'Taenia megalops" was also present. In Iceland 

 Krabbe collected numerous young specimens of T. rhomboidea 

 from wild ducks (A. boschas fera); they were 10"im long by 

 O.omm broad; the rostellum was armed with 10 hooks, 47 " 

 to 58 /i long; genital apparatus not visible. Friis (Krabbe, 1869) 

 collected the same species in Schleswig, and Krabbe thinks 

 that the worm which Molin (1858, p. 139; 1861, p. 253, Taf. VII, 

 figs. 1-2 )found in wild ducks in Padua and described under the 

 name T. conica is also identical with Dujardin's T. rhomboidea. 

 Molin 'records his form from Anas boschas; von Linstow (1878) 

 gives it for A. boschas dom., but not for A. boschas. Railliet 

 (1893, p. 303) places T. rhomboidea in the genus Dicranotaenia, 

 and calls attention to the error in Diesing (1850 p. 543) of in- 

 cluding T. trilineata as a parasite of the domestic duck — an 

 error repeated by von Linstow Railliet thinks that T. Trilineata 

 Batsch, 17S6, is identical with T. rhomboidea, although Du- 

 jardin (1S45) thinks that T. trilineata is simply a variety of T. 

 sinuosa. 



There seems no way either to prove or disprove what species 

 T. trilineata Batsch (=T. lineata Bloch) really represents, un- 

 less the types can be procured. In view of the poor descriptions 

 T intend for the present to ignore these specific names entirely. 



b. Genital pores alternate. 



9. DICRANOTAENIA SPHENOIDES (RaU'.Iet, 1892) Railliet, 1896. 

 (1872, Taenia cuneata von Linstow [nee Batsch, 1786 1; 189-, T. 

 sphenoides Raill.; 1893, Dicranotaenia cuneata (von Linstow, 

 1872) Raill.) 



[PI. IV, figs. 37-42.] 

 Diagnosis: Body 2mm (von Linstow) to 4mni (Magalhaes) long. 



lineata should never have been proposed, and hence can not 

 be taken into consideration under any circumstances. Krabbe 

 states that the description and figures of T. lineata are so im- 

 perfect that it is not possible to determine the species with 

 certainty, although fro-m Bloch's figures it is not probable that 

 his worm is identical with T. rhomboidea. This statement re- 

 lieves us from considering T. lineata further unless Blooh's 

 specimens can be found. Authors have generally accepted 

 Dujardin's specific name, but the publication of Nitzsch's name 

 by Rudolphi establishes the date of T. furcigera as 1819. and 

 associates the name with Rudoplhi's description. Krabbe's es- 

 tablishment of the identity of T. rhomboidea with T. furcigera 

 must naturally suppress Dujardin's name. Accordingly. 

 Nitzsch's specimens are the oldest types as yet consulted, 

 and nothing remains at present but to accept Rudolphi's pub- 

 lication of this name 



