CHAOTIC FUSIONS. “Diploids often produce cytologically unreduced female gametes, these unreduced gametes can fuse with normal haploid gametes (pollen) to generate triploid hybrids and, even more rarely, fuse with other unreduced gametes to produce tetraploids (having four copies of a single genome).”
http://libres.uncg.edu/ir/asu/f/Mueller,%20Marissa%20Thesis.pdf