SEA-FISHERIES LABORATORY. 85 



sprats the oil amounted to 11-10 per cent., and the water to 

 73-76 per cent. In the herring the amount of oil present was 

 2-61 per cent, and 80-27 per cent, of water. 



V. Food of Port Erin Herring. 



Three stomachs from a sample of herring landed at 

 Port Erin on July 5th, 1916. were sent to me for examination 

 by Dr. Johnstone. The following are the results : — 



No. 1 and No. 3. No. 2. 



Calanus finmarchicus, Calanus finmarcliicus, rare. 



common. Candacia armata, 1 only. 



Candacia armata, 1 only. Meganyctiphanes, a few. 



Larval decapods, a few. Larval decapods, rare. 



„ schizopods, a few. „ schizopods, common. 



Young clupeoid, remains. 



VI. Whitebait Collected in Menai Strait . 



This investigation on the material collected by Capt. R. 

 Jones is being continued. In my report for 1914 on this subject 

 it is suggested that there is a forward movement of the dorsal 

 fill in early stages of these young clupeoids. A more careful 

 analysis of the various measurements of the dorsal and pelvic 

 fins has recently been made. The new results indicate that 

 the displacement takes place in the pelvic appendages and 

 not in the dorsal fin in the case of the sprat, and in the dcrsal 

 fin in the case of the herrings. At a certain limiting age the 

 forward movement of the dorsal fin in the herring ceases. 



VII. Roosebeck Plaice Fishery of 1916. 



The plaice fishery at Roosebeck in the autumn of 1916 

 will probably long be remembered by the stake-net men for 

 its abundance and extraordinary money value. The late 



