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of 5,000 insects and terrestrial arthropods were also brought 
back. Scientifically, this Yucatan expedition may be counted 
as one of the more productive of the Bredin Caribbean expeditions. 
THE WEATHER 
Although the rainy season, with 50 to 60 inches of rain, 
runs from December to early May, and occasionally to mid-April, 
fine, clear weather proved the rule with us this year. The 
rains we did have seemed few and far between, but those that we 
experienced were proverbial tropical downpours, cloudbursts I 
want to say, for one got thoroughly soaked and chilled in them. 
Most of the time there were strong, persistent winds, 70 per cent 
of the time from the northeast, the sailing directions tell us, 
about half the time 10 to 12 miles an hour. A quarter of the 
time the winds ranged up to 20 or more miles an hour, but now 
and then a fierce squall would burst in suddenly from the north 
or west with winds up to 40 or more miles an hour. We found the 
days quite warm, in the low 80 T s in the shade, but the nights 
seemed always cool on deck because of the prevailing easterly 
trade winds. Though the recorded extremes of temperature for 
this coast are said to range from 39° to 107°, the average 
maximum is around 80°, the average minimum around 60°. 
A BIT OF HISTORY 
Ascension Bay, our chief collecting ground, was discovered 
by the Juan de Grijalva Expedi tion- -4 ships, 200 men--on 
Ascension Thursday, 1518. This expedition was also the first 
to see Tulum--as we first saw it — from the sea (Fig. ). 
Grijalva was on his way south along the east coast of Yucatan 
