290 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
October between 2,650 and 9,000; then on October 8th 
is a sudden rise to 33,970, a drop on October 9th to 
12,120, and a rise on October 12th to 39,000; 13th 
19,540; 14th 35,200; 15th 16,480; 16th 16,500; and then’ 
fluctuates between this and 11,958 until October 29th, 
when there is another rise to 23,780. November 2nd 
shows a drop to 19,065, and for the rest of the month the 
number fluctuates from 2,794 to 5,340. Finally the curve 
rises steadily from 5,925 on December 4th to 7,650 on 
December 50th. 
Fine Nets .—Starting on September 14th at 3,545 
the number drops suddenly on the 16th to 567 and on the 
l7th to 207; on the 21st rises to 4,640; then drops 
steadily to 251 on the 29th, but rises to 913 on the 30th; 
drops to 727 on October Ist, rises on the 2nd to 1,029; 
on the 5rd and 5th the numbers are 905 and 901 respec- 
tively. There is a sudden rise on October 6th to 12,560, 
a drop by three steps to 544 on October 9th, a rise by two 
steps to 1,895 on October 15th; drops again to less than 
600 on October 14th and 15th; a sudden rise to 2,880 on 
October 16th; drops to 468 on October 17th; 285 on the 
19th; 457 on 20th; 255 on 23rd; 941 on 24th; and 525 
on 26th. Then rises to 1,077 on 28th--then drops 
steadily to 160 on November 10th—this is doubled on the 
15th, but drops again to 94 on December 4th and rises 
through 121 to 261 on December 25rd. 
The first Copepod maximum is due to a sudden 
increase of the two species Pseudocalanus elongatus and 
Oithona similis. Without these species the numbers for 
March 17th and 21st and April 2nd respectively are only 
30, 26, and 140. The maximum in June is mainly 
composed of Otthona similis and Temora longicornis, in 
September of Pseudocalanus and Otthona, and in October 
of the same two forms with the addition of Acartia clausi. 
