Entozoa of British Marine Fishes. C7 



No Elasmobraiuh fishes arc noted in tliis paper, and of 

 the Telcostci, three j^roups — Pltaryugognathi, Lophol)ranchii, 

 and I'lcctognathi — are unrepresented. Of the reniainiii;^ three 

 groups upwards of GO species arc recorded from St. Andrews 

 Jiay, hut only .">() of these are at all common. About half 

 of these are dealt with here. A few yielded no parasites, a 

 notable case lieing Blimnius phulis, wliieh will be referred to 

 later; amongst the others an individual not harbouring its 

 quota of parasites was exceptional. 



A striking feature of the herein-noted results is the large 

 number of instances in which a parasite is recorded from a 

 new host, although the new species are few. Tliis may be 

 due to a particular host not having been examined before 

 or to its not having harboured Entozoa in the localities where 

 it had previously been examined. A third possibility sug- 

 gesting itself is that two species of fish may have been 

 confused or regarded as identical, and the parasites of one 

 attributed to the other. A case in point is that of Coitus 

 scorpius, Bloch, and C. bubalis, Euphr., between which 1 

 have sometimes found difficulty in deciding. I have, how- 

 ever, carefully compared each specimen examined with Day's 

 descriptions of the two species, and in so far as he is to be 

 depended upon the results may be regarded as correct. The 

 large number of forms new to Callus bubalis may be explained 

 in this way ; moreover, almost every one occurred in an 

 example which was unmistakably Coitus bubalis, Euphr. 



This leads us to a consideration of the work of previous 

 observers. Two most important attempts have been made 

 towards a systematic and exhaustive knowledge of the 

 Entozoa of the North Sea fishes — the one by Ulsson * in 

 18G7, the other by P. J. van Benedeu f in 1870. The work 

 of the former was done in the waters oti" the west coast of 

 Norway, which can hardly be regarded, strictly speaking, as 

 the North Sea; but since the majority of the species which 

 lie examined are common to our shores, we can include his 

 results under those for fish taken within the North Sea. 

 Van Benedeu drals Avith fish from the Belgian coast aud 

 from further out at sea. Both examined a very large number 

 of fishes, especially the commoner varieties. Amongst the 

 littoral fishes neither Olsson nor \'an Beneden makes mention 

 of Gobius Rullieusparri and Liparis Montayui. Olsson, in 

 addition, omits Zoarces viviparus ; Van Benedeu, Cuttus 



* *' Entozoa hos Skandiaaviska hafstiskar," Lunds Uiiiv. Arsslcrii't, 

 vol. iv. ltS«i7, no. viii. 



t " Lea I'ois.'Kjns des Cotes de Belgique," M^m. Ac«d. Belg. xxxviii. 

 1871. i 



