SEA-FISHERIES LABORATORY. 131 



Myxosporidian Infection in the Anarrichas lupus. 



A large catfish (Anarrichas lupus) sent to me by Mr. F. 

 Stokes was the subject of an extraordinarily rich infection by 

 a species of sporozoan. Dr. H. M. Woodcock, who saw some 

 of the tissue from this fish, identified the organism as a species 

 of Pleistophora, possibly new. Dr. H. C. Williamson* has also 

 described a similar condition in Anarrichas and regards the 

 parasite found as identical with Pleistophora hippoglossoides, 

 Bosanquet ; while Drewf also describes a new Pleistophora 

 from the muscles of the cod. It is not at all certain, however, 

 that the organism referred to here is identical with either of 

 those described by Williamson and Drew, and pending Dr. 

 Woodcock's investigation of its nature I only describe the 

 infection briefly. The whole fish, one about 27 inches in length, 

 was infected. All the flesh was knobby, as if large marbles 

 had been inserted some little distance beneath the integument. 

 On cutting into it, it was seen that these protuberances were 

 the result of the swelling of large blocks of muscle fibres, and 

 the swellings were also seen to be the result of the deposition 

 within the fibres of ripe cysts crowded with ripe spores. No 

 part of the flesh of this fish appeared to be quite free from 

 infection, but underneath the visible protuberances the 

 alteration of the normal muscle tissue was profound. The 

 ripely infected tissue was grey-green in colour and very soft, 

 so that on cutting into it it seemed to be fluid, a condition 

 due, probably, to the autolysis of the connective tissue remains 

 of the muscle fibres and bundles, and the liberation of the 

 ripened spores. 



Ovarian Degeneration in a Cod.— Plate III. 



In March of this year Mr. T. R. Bailey, Port Sanitary 

 Inspector at Fleetwood, sent me an ovary taken from a cod, 



* Ann. Report Fishery Board for Scotland Sci. Invest., 1911, II., (March, 

 1913), p. 16, PI. Ill, figs. 59-62. 



t Parasitology, Vol. II., 1909, p. 193, PI. 1. 



