11 



PAET II. 

 By Professor W. A. IIerdman. 



The Sea-Fish Hatching Experiments. 



In various previous reports I have referred to the import- 

 ance of instituting as soon as possible actual experiments 

 in sea-fish hatching in order to determine what can be 

 done in our own district in the artificial or semi-artificial 

 propagation of sea-fishes. As the Port Erin Biological 

 Station, belonging to the Liverpool Marine Biology Com- 

 mittee, offered in its Aquarimn house and tanks, and in 

 the specially pure sea-water off the south end of the Isle 

 of Man, special facilities for such observations, it was 

 decided to connnence the experimental work at that 

 establishment. An additional inducement to attempt 

 hatching first at Port Erin was the presence of an impor- 

 tant spawning ground within easy reach from which more 

 readily than in any other part of the district we could 

 obtain a supply of spawning fish, and ripe males. 



Accordingly with the help of a small grant to fit up 

 additional wooden tanks, we undertook, during the last 

 hatching season (Easter 1896), a series of observations 

 for the Lancashire Sea-Fisheries Committee. As the 

 result of these experiments we successfully fertilised the 

 eggs (obtained from the parent fish caught with the trawl) 

 of the grey Gurnard {Trigla gurnardus), the lemon Sole 

 {Pleuronectes microcephalus) , and the Witch {Pleuronectes 

 cynoglossiis), and kept them in the tanks until they 

 hatched out as young larvos. We were not prepared in 

 this first season to proceed with the rearing; but we 

 propose, with additional tanks and an improved circulation 



