= 3 = 
At the end of March we left Siam in the Danish steamer 
,Cathay* for Copenhagen, where we arrived on June 1 1900. 
Our collections have all been placed in the Botanical and Zoo- 
logical Museums of the University of Copenhagen. 
The island Koh Chang (Elephant Island) is situated in the 
northeasterly part of the Gulf of Siam about 80 miles from the 
boundary between Siam and Cambodia'). A strait, 2%/2— 10 
miles broad, separates the island from the Siamese mainland. The 
area of Koh Chang is about 70 square miles and it is the lar- 
gest Siamese island in the Bay. Consequent to its position in 12° 
lat. N. the climate of Koh Chang is entirely tropical, the year being 
divided in a rainy and a dry season, the former during the 
blowing of the damp south-west monsoon (generally from 
May to August) the latter in the other months where the dry 
north-easterly winds are prevalent. The heat is most ex- 
treme in spring, in March, April and May hefore the south- 
west monsoon sets in and after the cessation of the north-east. 
The coolest season is the autumn- and winter-months. At 
Bangkok?) the annual average temperature is 26,7° C. (80,1° 
F.), Decembers 24° C. (75,2° F.) and Aprils 28,5" C. (83,3° F.). 
The annual rainfall amounts to 1670™™ (65,7 inches) of which 
about */s during the months from May to October. 
The times of tides in the Gulf of Siam are very irregular 
and the rise also varies along the shores from 4 to 9 feet. In 
the Inner Gulf the principal of the two tides occurs in the south- 
west monsoon at night, but in the north-east this gradually 
alters and the high tide will be found in the daytime. 
Koh Chang is a mountainous island and ranges of peaks 
separated by valleys occupy its whole area especially running in 
the direction from NW to SE and growing in height and impor- 
tance as they go south. The highest point is found in the southern 
1) The more exact position is given by the following indications: Novthern- 
most point in 22°10’ lat. N., southernmost in 11°57’ lat. N., westmost 
in 102° 14’ long. E., eastmost in 102° 25’ long. E. 
2) Bangkok (13° 88" lat.N., 100° 34 long. E.) is the nearest place, from where 
some meteorological facts are present. During my stay in Koh Chang I 
made some measurements of temperatures and the degree of moisture, which 
later will be published. 
1* 
