176 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



not be laid on the above figures. Shrimps do not seem 

 to be so much affected. Captain Eccles informs ns, 

 however, that in his experience more shrimps are gener- 

 ally caught at springs than at neaps, on account of the 

 greater muddiness of the water during the higher tides. 



As regards the influence of the state of the tide as to 

 ebb and flow on the numbers of fish caught, much remains 

 to be made out. We have collected the hauls made during 

 every hour of the tide for the months -July, August, Sep- 

 tember, and calculated the average catches. The data 

 are rather incomplete, too few hauls having been made 

 just before high water to give satisfactory averages. The 

 results are set out in the table and on the accompanying 

 chart where the abscissae represent part of one daily tidal 

 cycle and the ordinates the average numbers of fishes 

 caught. 



Average catches of fish and shrimps made with a 

 shrimp trawl on the Mersey grounds during 

 July, August, September of the years 1893- 

 1902. Arranged for each hour of the tide. 



State of 

 Tide. 



No. of 

 Hauls. 



Soles. 



Plaice. 



Dabs. 



Whiting. 



2168 

 1165 

 1755 

 1590 



991 

 1527 

 1102 



677 

 2474 



Shrimps 

 (Quarts). 



H.W. to one 

 hour ebb ... 



1 to 2 hours 

 ebb 



4 

 10 

 14 

 10 

 13 



2 

 10 



7 



3 



140-7 



57 



46 



50 



95 

 288 



46 



82 

 102 



848 

 167 

 339 

 329 

 307 

 130 

 319 

 445 

 679 



421 

 412 

 650 

 776 

 530 

 1688 

 645 

 491 

 844 



20 

 11 



2 to 3 hours 

 ebb 



16 



3 to 4 hours 

 ebb 



14 



4 to 5 hours 

 ebb 



15 



5 hours ebb to 

 L.W 



22 



L.W. to 1 

 hour flood... 



1 to 2 hours 

 flood 



2 to 3 hours 

 flood ......... 



19 



14 



9 



