114 HtANSACTIQNS LIVERPOOL BIOLOGICAL SOCIETY. 



the present we have four species of Protozoa, ten species 

 of Yermes (Trematodes) and forty-six species of Crustacea 

 (Copepoda). 



The Protozoan parasites are found on and in various 

 parts of the fish, such as the brain, the intestines, and the 

 skin. In a few instances the presence of these parasites 

 is easily recognised, but in the majority, careful dissection 

 and examination of the tissues is required before they can 

 be detected. The most noteworthy appearance of the 

 presence of Protozoan parasites that has come under our 

 notice is the one on the skin of the ordinary " white fluke," 

 Pleuronectes flesus. It usually takes the form of small 

 white globular bodies attached to the skin of the body and 

 fins. In a specimen recently secured, the upper and lower 

 lips of the mouth were thickly covered with the cysts, 

 which doubtless interfered with the fish securing food. 

 The gills were also much infested. Occasionally larger 

 masses, sometimes the size of a marble, may be present. 

 This disease in the white fluke has attracted considerable 

 attention for many years, and is, no doubt, the origin of 

 the theory long held by fishermen that white flukes carried 

 their eggs attached to their body. We have a species of 

 Glur/ea recorded from the plaice, a Sporozoan from the 

 flounder, which is probably a new genus, also Glugea 

 lophii and another new form, Splicerospora platessce, which 

 infests the auditoiy capsule of the plaice. The two new 

 species will be discussed in another section of this Report, 

 in special papers by Mr. Woodcock. 



The Trematode parasites may be found attached to 

 the gills, or skin, and, in the case of one species, even in 

 the Cloaca. Occasionally more than one species may be 

 found attached to the gills of a single fish. These para- 

 sites are of various sizes, and usually colourless, except as 

 regards their excretory and reproductive systems. The 



