Orthotropous: In this type of ovule, the micropyle is at the distal end and the micropyle, the funicle and the chalaza lie in one straight vertical line. Examples: Piperaceae, Polygonaceae
Anatropous: The body of the ovule becomes completely inverted so that the micropyle and funiculus come to lie very close to each other. This is the common type of ovules found in dicots and monocots.
Hemianatropous: In this, the body of the ovule is placed transversely and at right angles to the funicle.
Example: Primulaceae.
Campylotropous: The body of the ovule at the micropylar end is curved and more or less bean shaped. The embryo sac is slightly curved. All the three:, hilum, micropyle and chalaza are adjacent to one another, with the micropyle oriented towards the placenta.
Example: Leguminosae.
Amphitropous: The distance between hilum and chalaza is less. The curvature of the ovule leads to horse-shoe shaped nucellus.
Example: some Alismataceae.
