Dr. L. Orley on Nematodes. 315 



VI. Genus Spiroptera, Linstovv. 



Spiroptera, Rud. (in part). 



Mouth-parts various in form ; two dissimilar spicula j eight 

 prseanal papillae. Bursa asymmetrical. 



No. Species. Species of host. 



1 . eurj-optera, Mud. Lanius minor. 



2. adunca, Crepl. Larus argentatus. 



3. crassicauda, Melilis. Colymbus septentrionalis. 



VII. Genus ACtAMONEMA, Dies. 



No constant characters can be assigned ; contains young 

 forms of Nematodes, which are chiefly to be found encysted in 

 fishes. No good species exist ; those assigned to it were 

 established by the older investigators. 



No, Species. Species of host. 



( Labrax lupus. 



-, • r.- ! Aphanopus carbo. 



1. communis, Dies. ■{ t^ ^ t. 



(jradus morrhua. 



(^Salmo salar. 



2. bicolor, Dies. Osmerus eperlanus. 



3. capsularia, Dies. Clupca alosa. 



„ ,, Merlucius Valparaiso. 



VIII. Genus Ancyracanthus, Dies. 



Mouth-parts various in form. Mouth-opening small ; two 

 dissimilar spicula ; from fifteen to twenty papillje, arranged in 

 a line singly or in pairs. 



No. Species. Species of host. 



1. cystidicola, Rud. Salmo fario. 



2. impar, Rud. (?). ,, ,, 



IX. Genus IIedruris, Creplin. 



Head with four lips ; two dissimilar spicula ; two praeanal 

 papillas. 



No. Species. Species of host. 



1. androphora, Kitsch. Triton cristatus. 



2. siredonis, Baird. Siredon mcxicanus. 



X. Genus CUCULLANUS, Miiller, 

 The mouth traverses the entire breadth of the head in the 



