Common Gull canus adult, June 02 2003, Vuurtorenvlakte, Maasvlakte, the Netherlands.

An individual hit by a car last week (died less than 7 days ago) just before the start of the complete moult. The upper-parts are medium grey, measured 5.5 at a 20 steps AGFA grey scale. The adult primaries have a clear-cut black triangle on the outer-wing. Black sub-terminal markings run down to P5 on this individual. From P1-P9 the primaries show extensive white tips and canus has two obvious mirrors on P9 and P10 (there may even be a small mirror on P8 as this individual shows). 
Adult brachyrhychus from the U.S. normally have a black sub-terminal band on P5-P10. Between this black band and the grey centre, a large white spot is visible both from above and below on P5-P7, creating a string of pearls on these primaries. P9 and P10 show large white mirrors.