SEA-FISHERIES LABORATORY. 291 



enormous haul of 151,220,000 on May 4th. As pointed 

 out above, 148 millions of this total belong" to the species 

 C. debile. After the middle of May the numbers rapidly 

 fell off' to a few tens or hundreds in August. They 

 rose again in September, and reached 1,792,200 on 

 October 9th. 



Coscinodiscus. — This genus was more abundant both 

 at the time of the spring and the autumn maximum than 

 in any previous recorded year. The maximum was on 

 April 30th, with 930,000 in the standard haul,, and in 

 October we had 102,000, on the 18th, and on November 

 3rd 83,000. The genus was practically unrepresented in 

 our nets from the middle of June till the beginning of 

 October. 



Ithizosolenia. — The highest monthly average 

 (2,013,916) was, as usual, in June (in 1913 it was in 

 July, but in every other year in June), but the actual 

 maximum was on July 2nd with 6,726,000. The genus 

 was entirely absent from our gatherings after July 16th 

 until October 12th, from which date till the end of the 

 year the largest haul was only 6,000 (October 18th). 

 Only in 1908 have the autumn numbers for Rhizosolenia 

 been lower than in this year. 



Thalassiosiva. — This genus was less abundant in 

 1914 than in the previous four years, but the numbers 

 were higher than in 1907-9. It appeared in our nets for 

 the first time in the middle of March (with the exception 

 of 20 specimens in one haul in January), and the numbers 

 increased to the maximum of 750,600 on May 7th, and 

 then fell to zero by the end of the month. It was 

 represented again from October 9th to 23rd (15,000 on 

 October 15th), and on two occasions in November (1,000 

 on the 9th, 300 on the 33rd), and was then absent for the 

 rest of the year. 



