(2 images) Larus fuscus fuscus 3cy HT-233.009, July 10-12 2003, Tampere, Finland (61.33N 24.59E).

Larus fuscus fuscus in 2cy often returns with completely replaced primaries and secondaries. In 3cy, fuscus more often shows a clear division between fresh inner primaries and older outer primaries, the inner primaries often showing neat white tips and the outer primaries often second generation-like with rounded tips and paler bleached brown. The arrested moult in the primaries is often reflected in the secondaries and (to a less extend) in the tail-feathers as well. The older tail-feathers (often R5 is older) still show a broad dark sub-terminal band.
3cy fuscus often have some black markings on the bill, which is otherwise much adult-like, with a clear red gonydeal spot. The colour of the naked parts are adult-like as well. 
The scapulars in 3cy are often completely adult-like, lacking internal patterns; plain blackish grey with a mahogany hue on the older feathers. Most wing-coverts and tertials are adult-like blackish grey as well, but often 3cy birds show some very bleached pale brown wing-coverts, normally in the greater covert bar and in the upper rows of the lesser coverts. These bleached wing-coverts accentuate the jumpy sequence in the last wing-covert moult cycles, as there is often no clear pattern in location of these bleached feathers. Head and body feathers normally are snow-white by July.

Ht-233.009 was ringed in Finland, now in 3cy. Primary moult was arrested at P7, leaving a clear division with the three outer primaries, P8-P10. Note the white mirror on the second generation P10.