to Leuckart, 1842 is not correct. According to Sproston, Leuckart in- 

 dicates the Cod --Gadus morrhua as a host of Octobothrium ( = Diclidophora) 

 palmatum, whereas actually in the works cited the question is about Gadus 

 molvae, that is Molva molva, which is the common host of D, palnnata. 

 The question about the finding of this genus on Hippoglossus hippoglossus p. 227 

 is more complex. The data of Rathke (Rathke, 1843) about the finding of 

 the parasite which was described by him as the new species, Octobothrium 

 digitatum Rathke on the Paltus serve as a basis for this indication. In his 

 "Systema Helminthum" Diesing (Diesing, 1850) placed this species as 

 synonymous to D. palmata without any explanation. Until the present time 

 this has been accepted by all authors as the actual relations in spite of the 

 fact that no one ever found D. palamata on the Paltus just as (they found no, 

 nobis) other species of this genus. We find the only indication of certain 

 doubt concerning these deductions in the work of Cerfontaine (Cerfontaine, 

 1895b) where the opinion of Van Beneden, who considers it unlikely that the 

 worms discovered by Rathke on the Paltus refer to D. palmata , is repro- 

 duced in a footnote. We consider the opinion cf Van Beneden completely 

 correct in that one must not make Octobothrium digitatum Rathke synony- 

 nnous with D. palmata (Leuckart). For the time being this species must be 

 left without precise generic identification but as independent though de- 

 manding redescription after new findings. We think that during verification 

 it will appear to be more likely as a representative of the genus Hetero - 

 bothrium or of one close to it. Thus, D. palmata must be placed with the 

 group of species which are encountered on one species of host and not on 

 several and especially of different orders. 



In the literature, Diclidophora merlangi is indicated from the 

 gills of Odontogadus merlangus (L. ) and Micromesistius poutassou (Risso) 

 (Gadidae, Gadiformes), and also from the isopod Cymothoa oestroides Risso 

 from the buccal cavity of Box boops (L. ) (Sparidae, Perciformes). One 

 can definitely consider the last indication as erroneous, for the structure 

 of the attaching disc of D. merlangi does not permit this species to attach 

 to the body of isopods and thus there is a mistake here in classification. 

 As regards the finding of D. merlangi onMicromesistius, it is more pro- 

 bable that here mistaken classification has also occurred [usually a close iiost]. 

 species--D. minor (Olsson)--is encountered on the last host . However, 

 if one is to recognize the correctness of the corresponding data both species 

 of hosts are related to close genera of the sanne family. Hence, ^. merlangi 

 must be considered as existing either on two close genera or even on one 

 species of host. 



Only Calicotyle kroyeri Diesing is indicated on many species 

 of fishes of two genera related to different orders. It is indicated on a 

 whole series of species of Raja (Rajidae, Rajiformes) and on Rhombus 

 maximus (L. ) (Bothidae, Pleuronectiformes). ^ The only indication pointing 



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