SEA-FISHERIES LABORATORY. 121 



Eudactylina acanthii, A. Scott. 



Of frequent occurrence on the gills of the picked 

 dog-fish. Tan Beneden records Eudactylina acuta from 

 the angel-fish and the picked dog-fish, but we have never 

 seen it on the latter. The present species is very distinct 

 from E. acuta. Another species, E. similis, T. Scott, from 

 the gills of Raia radiata, and a fourth from the gills of 

 Tiygon are known, but, so far, have not been met with 

 in the Irish Sea. 



Lemceenicus sprattce (Sowerby). 



Anchored in the eyes of the sprat, Clupea sprattus; 

 not very common, but one or two specimens are 

 frequently found in each catch of sprats. Usually only 

 one specimen is found on a fish; occasionally two, one 

 on each eye. We once met with a sprat that had two 

 parasites in one eye and one in the other. The parasite 

 measures 18 millimetres in length without the long egg- 

 sacs, but when these are added the length may reach to 

 one and three-fourth inches. 



Lerjiaenicus musteli, van Beneden. 



On the gill rakers of the smooth-hound, Squalus 

 mustelus. It is a large species, but does not appear to be 

 a common one. 



Lernaa hrancJiialis, Linn. 



This well-known and easily recognised parasite is 

 moderately common on the gills of various members of 

 the Gradida?. The cyclops stage is often abundant on the 

 extremities of the gills of plaice and flounder, and the 

 next stage is occasionally taken in tow-net collections. An 

 account of this curious form, and the changes that take 

 place before it reaches maturity, have already been given 

 in the Fisheries' Laboratory Eeport for 1900. 



