302 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



August 15, '07 = 25 ; August 19, '08 = 50 : August 20, 

 '08 = 35 ; August 26, '08 = 34 ; September 12, '08 = 

 38 and 37; September 15, '08 = 120; September 19, '07 

 = 85 ; September 20, '07 = 95 and 65 ; October 7, '08 

 = 65. Most, but not all, of these large hauls were taken 

 with the shear net or the large Xansen. If we take the 

 shear net as equivalent to 15, and the large Hansen 

 (100 cm. diam.) as equivalent to 10 of the small ordinary 

 nets, and make out monthly averages per unit net, it is 

 clear that the maximum occurs in October in the three 

 years taken together, and the same result is obtained 

 if we eliminate all the catches with larger nets and with 

 deep nets in the open sea, and take into consideration only 

 the hauls with the small open tow-net across Port Erin 

 Bay. There were 515 of these, representing every month 

 in each of the three years, and when combined they give 

 the following averages per net: — 



Jan. ... 0-6 April ... 0-1 July ... 0-5 Oct. ... 2-0 

 Feb. ... 0-1 May ... Aug. ... 0-7 Nov. ... 0-8 



Mar June ... 0-1 Sept. ... 0-8 Dec. ... 0-9 



Although in '09 Tomoj)teris is more fully repre- 

 sented throughout the year, still nearly twice as many 

 specimens per haul were obtained in '07, and nearly thrice 

 as many in '08. The figures for the three years separately 

 are as follows : — 



Total hauls Average No. 



Total hauls. in which Total No. of Average No. in hauls 



Tomopteris Tomopteris. in all hauls. where 

 occurs. represented. 



1907 



1908 



1909 



610 

 571 

 754 



63 

 103 



89 



399 

 945 

 339 



65 

 1-65 



0-45 



6-3 



9-17 



3-8 



3 years 



1,935 



255 



1,683 



0-87 



6-6 



