According to L&F Funcken, the Chasseurs Alpin adopted the horizon blue coat in 1915 and wore it over their dark blue tunic. They don't seem to have been issued with the Adrian, whereas the Chasseurs a Pied were. Haven't found many references but the enclosed is supposed to be an attack by Chasseurs Alpin on a German Customs Post in 1918. Artists' illustrations always suspect, as we know, but this is the best I can do at the moment.
Spencer Coil's book has no references to Chasseurs Alpin wearing anything but the beret, or tarte, throughout the War.
"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.
