It is from the first season,the episode where 
Miaka is bathing in the woods on the way to 
Taitskun's castle.  She is in the water and 
thinks something has grabbed her- this just 
before she and Tamahome make up when he rescues 
her from... a log.  ^_^  
It's episode 5- I have a cel of Miaka from that 
episode, earlier in the day.  My favorite Miaka 
cel actually.