Gadfly Layer Order (Geom.point and Geom.line)

Specific Domains Visualization
10

Tried your code. Removed dependency on Colors and simplified a bit - still works. Basically using Scale.color_discrete_manual to control the color. Excellent.

#using Colors
#cs = ["fn1", "0.3x+1", "0.3x+1.1"]
#dpalette(n::Int) = LCHuv.(65, 100, 15:(360/n):374)
palette2 = ["deepskyblue","yellow3", "hotpink", "blue", "orange", "orchid"]

p = plot(iris,
    layer(x=:SepalLength, y=:SepalWidth, color=:Species),
    #layer(y=fs, xmin=[4.4], xmax=[8], Stat.func, Geom.line, color=cs, order=2),
    layer(y=fs, xmin=[4.4], xmax=[8], Stat.func, Geom.line, order=2),
#    Scale.color_discrete_manual(dpalette(6)...) 
   Scale.color_discrete_manual(palette2...), 
    Guide.colorkey(title="Iris")
    )