sea-fisheries laboratory. 303 



Sagitta. 



Sagitta is represented in all months. The numbers 

 keep low (under 50) from January to April inclusive, and 

 then advance to over 200 late in May, over 500 on 

 June 4th, 1,975 and 1,344 on June 9th, 1,012 on June 18th, 

 over 400 late in July and early in August, after which the 

 numbers run rapidly down to under 30, and then remain 

 for the most part at units during September and October. 

 In November the highest number is 115, and in December 

 104. The smoothed curve representing monthly averages 

 shows, then, one great peak in June and slighter eleva- 

 tions late in July and early in August, and again in 

 November and December. The minima are in the first 

 four months of the year and in September and October. 

 The addition of the catches made in the sea outside the 

 bay during April and in summer does not materially 

 affect the general shape of the curve. 



When we compare these results with those of the two 

 previous years, we find that although each year has some 

 peculiarities, there is a general similarity. In '07 there 

 was a maximum in July- August and a second lower peak 

 in October-November. In '08, when the numbers as a 

 whole were lower, there was a maximum in the open sea 

 on August 7th, and again early in November. Combining 

 the three years, we find two distinct maxima in the year, 

 the first, greater one, in June- August, and the second, 

 much smaller, in October-November. Looking at the 

 largest hauls in each year, in the ordinary tow-nets we 

 find: — 



In '07 : On August 12th, 1,000 ; on August 15th, 1,800 ; 

 and on November 4th, 324. 



In '08: On June 30th, 750; on August 7th, 256; on 

 September 14th, 220; and on November 6th, 108. 



u 



