Juday—Lakes in Central America. 215 
a dry or winter season which lasts from November until April, 
and a wet season from May to October. December and January 
are the coldest months of the year.' During the period covered 
by these studies the prevailing winds blew from the southwest 
and at such times there was always very little or no wind at all 
during the earlier part of the day, but between 10 a. m. and noon 
a southwesterly wind would spring up and blow until about sun¬ 
set, reaching a maximum strength about the middle of the after¬ 
noon. Cool northerly winds were noted twice. At lake Atitlan 
a strong northerly wind arose about noon on February 12 and 
blew continuously for a little more than three days, making the 
lake, so rough that work had to be discontinued during this in¬ 
terval of time. A few days later another norther, called 
‘ ‘ norte 7 7 by the natives, was noted at lake Coatepeque. 
Some idea of the daily range of the temperature of the air at 
two of the lakes during the visits may be obtained from the fol¬ 
lowing table: 
Table I. Air Temperatures at Lakes Atitlan and Ilopango. 
Lake Atitlan 
Lake Ilopangro 
Day 
Hour 
Temp. 
Day 
Hour 
Temp. 
Feb. 13 . 
5:30 p. m. 
21.1° C. 
Feb. 21. 
noon 
27.0° C. 
0:00 p. m. 
19.4 
2:00 p. m. 
27.5 
14.. 
6:30 a. m. 
17.2 
6:00 p. m. 
26.1 
1:30 p. m. 
25.0 
22. 
6:30 a. m. 
21.4 
6:00 p. m. 
20.0 
2:30 p. m. 
30.5 
9:00 p. m. 
16.0 
6:05 p. m. 
21.1 
15. 
6:00 a. m. 
17.2 
9:00 p. m. 
21.1 
1:30 p. m. 
22.3 
23. 
6:00 a. m. 
17.0 
6:00 p. m. 
21.0 
noon 
29.4 
9:00 p. m. 
19.5 
1:00 p. m. 
29.3 
16. 
6:15 a. m. 
16.4 
3:00p. m. 
28.6 
1:30 p. m. 
21.3 
9:00 p. m. 
16.2 
17. 
6:00 a. m. 
11.8 
At lake Amatitlan in the latter part of January, 1906, Meek 1 
found by means of maximum and minimum self-registering ther¬ 
mometers that the lowest temperatures of the day were reached 
between 3 a. m. and 5 a. m. and the highest between 2 p. m. and 
4 p. m. The total range varied from a minimum of 11.7° C. 
(53° Fahr.) to a maximum of 26.1° C. (79° Fahr.) 
1 Field Columbian Museum, ZooL, Vol. VII, p. 178. 1908. «, 
) 
