
599U at the top is a normal pied ringneck squab. Its nestmate, 599V at the bottom, is a pied flare mutant squab. The short down shows the pterolography very well and is unmistakable. Photos were taken in 1984.

599V grew into this two months old, blond pied flare. Note the wing tips and tail tips flared out. The contour feathers are normal. This is a recessive mutant which is now "lost".
Another view of 599V flare mutant. 40% of such
mutants die early. In full adult plumage the bird looks entirely
normal!