1912] Esterly: Copepoda of the San Diego Region 299 
TABLE 25 
Distribution of Bucalanus at surface with regard to temperature 
A. 4-8 a.m. 
No. of hauls No. of hours No. of animals Frequency 
Temperature Total Success. Total Success. Total Perhour Haul Time 
y 3 4 5 6 7 8 
1. 16°0-17°0 16 3 11.9 1.2 5 0.45 19 9 
2. 1721-1870 15 2 14.0 4.0 44 3.1 13 21 
18°1-19°0 10 1 6.4 0.35 6 0.93, 10 5 
Iya 7AlaG) 14 5 6.8 1.6 45 6.6 51 23 
1. 1620-1720 10 0 0 0 0 0 0 0 
2. 1721-1870 8 2 4.5 0.66 16 BY) 25 14 
3. 18°1-19°0 6 0 3.2 0 0 0 0 0 
4, 19°1-21°5 it 2 6.8 1.0 15 2.2 28 15 
C. 4-10 p.m. 
1. .16°0-17°0 1 1 0.42 0.42 81 194.0 100 100 
2. 17°21-18°0 6 3 5.6 4.4 3 0.5 50 79 
3. 18°1-19°0 9 0 7.5 0 0 0 0 0 
19°1-21°5 17 ii 8.3 41 372 44.8 41 49 
1. 1620-1720 4 3 3.4 2.5 56 16.5 75 74 
2. 17°1-18°0 3 1 2.9 058 oT 19.6 33 20 
18?1-19°0 3 0 5.0 0 0 0 0 0 
1971-2175 1 0 1.0 0 0 0 0 0 
The only conclusion that is justifiable from the above data 
is that the distribution of Hucalanus is unrelated to the surface 
temperature. For example, the highest average per hour in 
section A is at a temperature from 1921 to 2125; in section B 
the high average is obtained when the temperature varies from 
1721 to 18° In other words, we find that the relation between 
temperature and abundance varies with the time of day. This 
should be taken to mean, in my opinion, that whatever the 
effective factor is in determining distribution, temperatures 
within the limits observed at the surface are practically neg. 
ligible. It may be pointed out as a matter of interest that 
only one haul out of twenty-eight took Eucalanus when the 
temperature was 1821-19° (table 25, line 3 of all the sections). 
