•4 Dr. \V. Nicoll on the 



follows:— I. = rarely (luuler 10 per cent.); II. = occasionally 

 (10-25 per cent.); 1 II. = commonly (25-50 per cent.); 

 lV. = frcquently (50-75 per cent.) ; V. = very frequently (over 

 75 percent.) ; 1 = 1 or 2 at a time; 2 = less than 10; 3 = 

 less than 50 ; 4 = 50-100 ; 5 = over 100. Thus IV. 2 will be 

 taken to indicate that a parasite occurs frequently in numbers 

 less than ten in each host, as in the case of Podocotyle atomon. 

 The fish in this part are named according to ' A History of 

 Scandinavian Fishes,' by Fries, Ekstrom, and Sundevall. 



ACANTHOPTEEYGII. 



Trachinus vipera, Cuv. Lesser Weaver. 



Ascaris capsularia, Rud. (juven.). 

 Cottus scorpius, Bloch. Bullhead. 



Slephanochasmus baccatus, Nicoll, 



Heniiurus communis, Odhn. 

 Cottus bubalis, Eupbr. Father-lasher. 



Ucmiurus communis, Odhn. 

 (= H. appendiculatus, viihi.) 



Ascaris angulata, Hud. 

 Agoiius cataphractus (Linn.). Pogge. 



Scolex polymorphus, Rud. 



Ascaris sp. 



Ascaris cummunis, Dies. (juv.). 

 Callionymus lyra, Linn. Dragonet. 



(Lehouria) alacris, Lss. 



ZoogoDoides viviparus (Olss.). 



Derogenes varicus {Muller). 



Lecitnaster gibbosus (Rud.). 



Scolex polymorphus, Rud. 



Ascaris sp. 



Heterakis foveolata, Rud. 

 Trigla gurnardus, Linn. Grey Gurnard. 



Slephanochasmus triglse, Lebour. 



Derogenes varicus (Muller) (juven.). 



Hemiurus communis, Odhn. 



Hemiurus liihei, Odhn. 



Gasterostomum triglse, v. Ben. 



Scolex polymorphus, Rtid. 



Ascaris sp. 



Ascaris capsularia, Rud. (juven.). 

 Cyclopterris lumpus, Linn. Lumpsucker. 



Dibtomum sp. (juven.). 



Scolex polymorphus. 



Ascaris sp. 



Ascaris capsularia, Rud. (juven.). 

 Liparis montagui, Donov. Montague's Sucker 



Scolex polymorphus, Rud. 

 Anarrhichas lupus, Linn. Catfish. 



Lebouria idonea, Nicoll. 



(Acanthopeolus) anarrhichae, sp. inq. 



