Enlozoa of BritUh Marine Fishet. [\ 



nuittis, Steringophorti$ furciger^ PoJocotyte alonion, Lfftidi' 

 pedon {LffXHiora) rachiacum^ l^ecitluisUr gihboatu^ and JJero- 

 genfs varicua. Since then Mii^s Lcbour's work* on " Fiali 

 riTni:itoilt'3 of the Ni)rthuinl)erhintl Const " has appcareil, 

 and this is the most coniprchonsive jittoinpt which has yet 

 been niado to dcjil with fi-nh tV<)in liiitish waters. Frequent 

 reforonce will bo made to both these works in the following 

 notes. 



One of the most reninrknble contrasts between Miss Lcbour'a 

 results and those obtaineii at St. Andrews is evidenced in 

 the occurrence of I'odocotyle atoinun. Special notice was 

 made ot this species in Purl I. Of all the conunoii rock-tish 

 at St. Andrews only two, the shaniiy [lilenntus phul'iH) and 

 the pofijge {Agoutis cataphractus) have nut been found to 

 harbour this parasite. Ten other species of rock-fish contain 

 it as frequently as 71 per cent. On the Northuinbcrland 

 coast the Ircquency is only 3 per cent., Cuttus scorpius being 

 the sole host. 



I have examined all the species of rock-fish with which 

 Miss Lebotir deals except Onos cimbrius, and have found 

 Fodocotyle atomon in every one of them. I have also had 

 occasion to examine the rock-fish in the Firth of Clyde, and 

 there the j)arasite was found in 57 per cent. There al^^o it 

 occurred vorv frequently in the saithe (Gadtis vi'rens) and 

 lythe {(j. pollachius), and, in acMition, in the dab and plaice. 

 In the case of the Northumberland coast we appear to bo 

 confronted with a local peculiarity, the explanation of which 

 is not at present obvious. A point of interest lies in the fact 

 that the rock-fish examined by Miss Lebour were not infected, 

 with the exception of Coitus scorpius, with Trematode para- 

 sites of any kind. Several other Trematodes occur in the 

 rock-fishes at St. Andrews, e. g. Derogenes various, Ilemiurus 

 comrnunis, Slrphanochasinus baccatus, and Prosorlnjnchus 

 squamatus. Two of these were found by Miss Lebour in 

 Coitus scorpius. 



No case similar to that of Dlennius pholis t has again 

 been met wiih. The only three species from which no 

 parasites were obtained were Merlucius nierluccius, Chimcera 

 motibtrosa, and Gvhius minutus ; but only one or two 

 specimens of each of these were examined. 



In the following list an attempt is made to indicate with 

 what frequency and in what numbers the various parasites 

 occur in each host. For that purpose fi^^ures are used as 



• ' Northumberland Sea FUheriea Rt>port ' for 1907 (1908), pp. 23 67. 

 t Part I.. Ann. & Mn? Nat. Hist. (7) xix. p. 6S. 



1* 



