ARUM FAMILY 



63 



actually gives off heat, so that the temperature 

 inside the blossom is higher than it is outside, 

 even when the wind is not blowing. Conse- 



FLOWERS OF SWAMP CABBAGE 



quently it is not strange that the flies seek such 

 snug retreats when the sun is hidden by clouds, 

 but come out again when it shines once more. 



