TkEMATOtES OF THE NoRThUmBeRLANId COAST 4I 



A far more likely adult seems to be Stephanochasmus baccahis, 

 Nicoll'-', from the Halibut Hippoglosstis vt/lga?-ts, Flem. This 

 worm has 56 head spines, the lower row being longer than the 

 upper and uninterrupted. The prepharynx is very short, but 

 this is probably due to the action of the preserving medium, 

 and this may also account for the shortness of the body. 

 The reproductive organs, not being fully developed in the 

 larval form, cannot very well be compared with those of 

 Nicoll's specimen. The above characteristics of the head 

 warrant, I think, this worm being provisionally looked upon 

 as the larval form of Stephanochasmus baccaius. The variation 

 in the head spines is interesting, especially as Monticellij 

 thought those of his larval forms from Box salpa and Rhombus 

 IcEvis were also variable. On the other hand Loos|, in all the 

 adults described, finds the number of head spines generally 

 constant for each species. 



Derogenes various (O. F. Mlill.) occurs in many of the 

 local fish, and is perhaps the commonest Trematode from our 

 coast. The host in which I have found it in greatest numbers 

 is the Long Rough Dab, chiefly in the mouth and on the gills, 

 but sometimes in the oesophagus, stomach, and intestine. 

 Odhner§ considers that its presence in the gills is perhaps due 

 to the wandering of the parasite after the death of the host, 

 the true habitat being the stomach. I believe, however, the 

 mouth and gills of the Long Rough Dab to be quite as much 

 the true habitat for the Vvorm as the stomach. 



On a specimen of Derogenes varicus taken from the mouth 

 of the above-mentioned fish in June, 1907, I found clinging to 

 it a parasitic Copepod (Plate IIL, fig. 2-3). The Copepod 

 was alive and clung firmly to the worm by two very large 

 hooks at the head end. Now a parasitic Copepod is not 

 likely to inhabit any part of the intestine of a fish, and I 



* NiroU. II'., "A Contribution towards a Knowledge of the Entozoa of British 

 Marine Fishes," Ann. and Mag. Nat. Hist., Ser. 7, Vol. XIX., 1907, p. 80. 

 t Op. cit,, p. 161. 

 % Loos, A., Op. cit. 

 § Odhner, T., Fauna Arctica, p. 3G0. 



