The name-typical form of ferrugata as figured by Clerck and well described by Linne, has the median band reddish or purplish, the distal area very weakly marked (except the costal patch and two dark spots between the radials) often almost entirely white or whitish.

is a very common and very interesting aberration which has been proved, by my very extensive breeding experiments and those of Dr. Draudt, to be an almost perfect Mendelian "recessive".

- bilbainensis Fuchs, from Bilbao, said to be a local race, is described as smaller, narrower-winged, the distal edge of the median band more distinctly biangulate.

— stupida Alph., from Issyk-kul, Tibet, W. Central China, etc., is rather larger, with whiter hindwing otherwise similar to ab.

The larvae feed on species of Galium, Stellaria, Campanula and Cirsium.