Freshly-emerged, early season Comma (yellow spots in orange border)
April colouring (form hutchinsoni)
Late season Comma (orange background in black border)
The Comma butterfly is instantly recognisable by its "ragged" wing outline, -- photos downgraded for internet
The side view shows the white "comma" mark that gives the butterfly its name
Above: Comma butterfly by Bob Clark (on his finger)
The new generation that will complete its life cycle in the same year has a lighter underside wing and those that are destined to hibernate through the winter and fly the following year are darker; both well-camouflaged as a dead leaf. Males have a more variegated underside and females a plainer one.
Link to Comma caterpillar (link not yet active)