8 GYLDENSTOLPE, BIRDS COLLECTED BY THE SWEDISH ZOOLOGICAL EXPEDITION TO SIAM. 



villages, are the only contrasts to the desolateness of the country, which is as a 

 rule totally treeless. 



South of the town of Pitsanulok the Northern Railway line passes through 

 miles and miles of big swamps and marshes, mostly covered by high grass and reeds. 

 Here and there there are also some pond-like lakes nearly always overgrown with 

 Lotus, Eichornia speciosa and several other water-plants. Such swamps are, of 

 conrse, a real »El Dorado» for wading- and swimming birds, especially during the 

 winter months with their immense quantities of migratory birds. During the rainy 

 season the whole country is flooded and the water stånds high up the road-bed, 

 nearly reaching the rails, and then the whole area of land looks like a great lake. 



Fig. 1. Vegetation near tlie iiiarslies at Tlia Law. 

 Photo. N. Gyldenstoi-pe. 



During the first lialf of April I stayed at the village of Tha Law, some miles 

 south of Pitsanulok. Tha Law is quite surrounded by these great swamps, and 

 was then a splendid centre for studying the bird fauna. Before reaching the real 

 swamps when going north from the village I liad to pass some small tobacco-fields 

 and patches of reed jungle. Even at a great distance blackish spöts could be ob- 

 served, moving slowly on the drier places. On closer inspection these spöts showed 

 themselves to be Adjutant storks {Leptoptilus dubius Gm.). At the slightest sign of 

 danger these hiduous birds flew away at first always circling for some time near the 

 ground and then escaping on majestical wings to the bambooclumpses in the vicinity 

 from which they had a good view of the surroundings. Among the brownish coloured 

 masses of reeds which covered the largest area of the swamps some green spöts could 

 also be seen and on these were hundreds and hundreds of white and grey herons 



