Ovule orientation may be anatropous, such that when inverted the micropyle faces the placenta (this is the most common ovule orientation in flowering plants), amphitropous, campylotropous, or orthotropous.
Campylotropous : When the ovule is curved, the micropyle is directed toward chaiaza. Chaiaza is situated at right angles to funicle e.g., Members of Leguminosae family. 5. Amphitropous : The ovule curvature is more pronounced and embryosac become horse-shoe shaped e.g., Families, Alismaceae, Butamaceae. 6.
Hemi-anatropous or hemitropous ovule The body of the ovule is placed transversely at right angles to the funicle. The micropyle and chalaza lie in one straight line e.g.Ranunculus.
Orthotropous or atropous ovule (ortho-straight, tropous - turn) The body of the ovule is erect or straight. The hilum, chalaza and the micropyle lie in a straight line e.g. Polygonum.