Only one of the four resulting megaspores survives. These plants have two spore types, megaspores and microspores. Typically, one cell in the megasporangium undergoes meiosis resulting in one to four megaspores. Individual plants are either male producing microspores or female producing megaspores. The embryo sac or megagametophyte is tetrasporic, in which all four megaspores survive. The megasporocyte undergoes a meiotic cell division, producing four haploid megaspores. The female cone develops two ovules, each of which contains haploid megaspores. Conifers are heterosporous, generating two different types of spores&colon; male microspores and female megaspores. The best way to identify them is by examining their megaspores under a microscope. The best way to identify them is by examining the megaspores under a microscope. "Selaginella apoda" megaspores may be dispersed by wind or water. The megaspores become megagametophytes (embryo sacs). A megasporocyte inside a megasporangium or ovule undergoes meiosis, producing four megaspores. Megaspores, also called macrospores, are a type of spore that is present in heterosporous plants. Megagametophytes develop from megaspores and are retained within the ovule.