Love this.

Nice! I especially like the water lillies, for some reason. :)

Something about the proportion of the way you draw heads is off, and I've been trying to figure it out for a while. I think I finally did - the shape of your hairline isn't right. We should see more of the hairline, not just where it goes across the forehead, but also where it starts coming down at the edge of the forehead, angling down towards the ear. With long hair hanging down, especially if it's pushed behind the shoulder, it usually only just covers the ear. So there should be a bit of space between the edge of the hair and the eyebrow, and even more space at the level of the cheekbone. We should see the corner of her jaw.

The general shape of the River-Woman's hairline is better, but again you aren't showing the roots of her hairline coming down towards the ear.

This photo shows a good example of what I'm trying to describe: http://www.gettyimages.com/detail/photo/profile-portrait-serene-brunette-indian-woman-royalty-free-image/697541223. The hair we see flowing down isn't just coming straight down from her part or the top of her head, we can also see it coming from her temple and above her hear. Also, you often just have their hair flowing from the top of their heads and no sign of a part, when most people's hair does part, especially if their hair is long.

(BTW, if you'd like me to stop with what is intended to be constructive criticism, please feel free to tell me at any time that it is not welcomed.)