184 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



It is probable that the conditions in these shallow 

 sanely channels which suit the shrimps are also the most 

 suitable conditions for young fish — especially flat fish — 

 in certain stages of growth, and consequently it is futile 

 to hope that any artificial operations will lead to the 

 separation of the two kinds of animals. 



Note on a Sporozoon Parasite of the Plaice. 



(Pleuronectes platessa). 



By James Johnstone. 



* (With Plate D.) 



Two specimens of plaice have come to the Fisheries 

 Laboratory during the year which showed a peculiar 

 modification of the intestinal wall. One specimen was 

 sent by Mr. G. Eccles, Chief Fishery Officer at ]N T ew 

 Brighton. It was caught near the Mersey Bar at the 

 beginning of October. The other was sent to me by Mr. 

 A. Scott. It had been caught by Mr. Wright, Fishery 

 Officer, in Barrow Channel, on October 1st, 1900. 



The first specimen was a female about 8 inches long. 

 It had been opened, and the head cut partly off. Mr. 

 Eccles was struck by the granular appearance of the 

 viscera, suggesting the presence of a large quantity of 

 spawn. As however the fish was much too small to con- 

 tain ripe ovaries, he thought it worth sending to the 

 Laboratory. It was fresh when it came to hand, and the 

 fish looked in good enough condition. The ovaries were 

 about one inch in length but perfectly normal for a fish 

 of this size. The intestine, liver, kidney, &c, had their 

 usual relations. 



But the greater portion of the intestine, from the 

 pylorus to about 1^ inches from the anus was thickened, 

 and had the appearance of a ripe ovary. That is, the 

 surface was studded with little round white opaque bodies 



