SEA-FISHERIES LABORATORY. 121 



relation to plaice from the same source. As in the former case 

 the liver was very extensively invaded by the fungus. 



Obviously a mere examination of the morphology of the 

 fungus as it occurs in these specimens is not sufficient for the 

 identification of the species. 



2. Tetrarhynchid larvae in the Plaice. 



Tetrarhynchid larvae were fairly numerous in the plaice 

 being adherent to the peritoneum over intestine and other 

 viscera. Fig. 6 represents one of these larvae dissected out 

 from its investments. It would be hazardous to attempt to 

 identify its species. The form and attachment of the larva are 

 similar in all respects to that given by me* in the general 

 description of the larvae of Tetrarhynchus erinaceus. I have 

 already found this species in the Plaice, and forms similar 

 to that mentioned here. 



3. Degenerate Cestode Larvae in Muscles of 



Hake. 



In June of 1916 Dr. W. M. Tattersall, keeper of the 

 Manchester Museum, sent to me a piece of a Hake " steak " 

 that had been seized by a fish inspector in the public market. 

 The flesh of the fish was greatly discoloured, black or dark 

 grey in numerous patches, and on looking at these closely 

 the discolouration was seen to be caused by very numerous, 

 minute, black streaks among the muscle fibres. 



Fig. 3 shows the appearance of the tissue when seen 



under a low magnification. The muscle fibres themselves are 



quite normal in structure, but lying among them are numbers 



of rod-like bodies, rather irregular in diameter, and usually 



with slightly swollen extremities. These arc of very various 



length, perhaps from one quarter to one and a half millimetres. 



Some of them lie across the muscle fibres, but as a rule they 



*" Tetrarhynchus erinaceua, van Beneden : Structure of larva and 

 adult worm," Parasitology, Vol. IV. No. I. pp. L912, 371-2. Cambridge. 



