This is the life cycle in which the diploid phase is followed by two dissimilar haploid generations.
In plants like Nemalion, Batrochospermum the gametophyte haploid plant produces the zygote during sexual fusion. This zygote undergoes meiosis and produces haploid carposporophyte which is parasitic to gametophyte. The carposporophyte produces haploid carpospores which germinate to form haploid gametophyte. Thus here there is only one diploid generation which is the zygote itself, while the haploid generation is represented by the independent gametophyte and the parasitic carposporophyte. This kind of life cycle is called haplobiontic type.