[Footnote 3: For a detailed discussion of the behaviour of the Blue Andalusian in breeding, the reader is referred to "The Mating and Breeding of Poultry" by Harry M. Lamon and Rob R. Slocum, published by the Orange Judd Publishing Company, New York City.] [Illustration: FIG. 12. Blue Swedish duck showing white flight feathers. The Standard calls for only two white flights, but there is a decided tendency as shown here for more flights to be white. (_Photograph from the Bureau of Animal Industry, U. S. Department of Agriculture._)] _The Crested White._ Although not so large, this breed is much like the Pekin but with body carried more nearly horizontal and with a crest on the head. The type varies considerably however, the principal selection practiced having been for crest. The plumage is white in color throughout. What is desired in the crest is to have as large a one as possible, round and perfect in form, and set squarely on the head. Not infrequently crooked crests occur and also double or split crests, that is to say, where the crest is parted or divided. In some cases the crests may even come treble, that is, split into three parts. Entire absence of crest is by no means uncommon. In fact, it is considered a pretty good proportion if one half of the ducks hatched have crests although the matings vary considerably in this, occasionally one producing practically 100% of the offspring with crests. Avoid as breeders birds with small crests, lopped crests, split crests or showing an absence of crest. Avoid also breeders showing mottled or green bills in females and black bean in the bill of drakes.