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MR. F. DAY ON THE FISHES 



[Dec. 2, 



If we divide the fishes captured in the years 1878 and 1879 into 

 families, we find as follows : — 



1878. 1879. 



Mullidse 1 2 



Sparidse 57 1 



Triglidaj 149 265 



Carangidse 113 28 



Gadidse 188 348 



Pleuronectidse . . . . 977 1954 



Muraenidse 43 6 



One cause which has great bearing upon the presence or absence 

 of certain kinds of fish is, as already observed, the temperature of 

 the sea. The following figures from Lord Ducie's notes show what 

 was the average temperature at the surface daily at 7 a.m. : — 



1878, July 63 August . . 618 



1879, „ .... 53-5 „ .. 56-8 



Consequently in July 1879 we find the temperature of the air was 

 4 0, 5 lower than the average of the mean temperature for the last 

 twenty years, and of the surface-water of the sea 9° - 5 less than in 

 1878 ; while in August the mean temperature of the air was 2 O- 

 less than the average for the last twenty years, and of the surface- 

 water of the sea 5° lower than in 1878. 



On July 21, 1878, at 12.30 a.m., the temperature of the sea is thus 

 recorded: — At surface, 71°; at 1 fathom, G7°"5 ; 2 fathoms, 66°; 



