_The White Muscovy._ This variety should have pure white plumage throughout. Young Muscovies of both sexes often have a patch of black on top of the head up to the time they moult at maturity. Since black disqualifies it is impossible to show young ducks in this condition but these black feathers usually come in white after the moult and such birds need not therefore be discarded as breeders. When it is desired to show young White Muscovies which have black on the head it is customary to pluck these black feathers a sufficient time before the show so that the white feathers which come in their place will have time to grow out. There is little or no trouble with black or gypsy face in this variety. [Illustration: FIG. 11. Upper--Crested White Drake. Lower--Young White Muscovy duck showing black on top of the head. This is not an unusual occurrence and the black is lost when the bird gets its mature plumage in the fall. (_Photographs from the Bureau of Animal Industry, U. S. Department of Agriculture._)] _The Blue Swedish._ In type and size this breed is about the same as the Cayuga although perhaps slightly more upstanding. In selecting the mating it is important to use birds which are close to standard weight as there is somewhat of a tendency for the size to be too small. As its name indicates the color is largely blue except for a white heart-shaped patch or bib which should be present on the breast. Sometimes this white extends along the underside of the body from the under-bill almost to the vent. Such birds are undesirable as breeders since they show too much white. On the other hand birds lacking a prominent white bib must also be avoided. Two of the flight feathers should be white and birds lacking these must be avoided. Guard against any red, gray or black in any part of the plumage. Sometimes, however, birds having more or less black throughout the plumage are used as breeders for the purpose of strengthening the blue color. Avoid any tendency toward a ribbon on the wing-bow and also birds that are too light, ashy or washed out in the blue color. Sometimes birds show lines of white feathers around the eyes and over the head and these should be selected against as breeders as they are likely to cause white splashing in the plumage. Yellow or greenish bills must likewise be avoided since the first of these is a disqualification. In general this variety in breeding behaves insofar as color is concerned, very much like the Blue Andalusian chicken.[3] The young ducks when hatched are yellow or creamy blue and from blue matings there are also produced black and white ducklings. As in other colored breeds and varieties, the dark pin feathers are somewhat of a disadvantage from a market standpoint.