Horse shoe shaped embryosac/nucellus is characteristic of

The ovule in embryo sac is so curved that it takes the shape of horse shoe in amphitropous ovule. In orthotropous ovule, micropyle, chalaza and funiculus are on the same straight line. In anatropous ovule, ovules are inverted and micropyle lies close to funiculus. In campylotropous ovule, micropyle comes towards the funiculus and the embryo sac is slightly curved.