Complex sentence: Submerged leaves bearing sori that are surrounded by basifixed membranous indusia (sporocarps); sporocarps of two types, bearing either megasporangia that are few in number (approximately 10), each with single megaspore, or many microsporangia, each with 64 microspores.
Split into simpler sentences: Submerged leaves bearing sori that are surrounded by basifixed membranous indusia (sporocarps). They bear sporocarps of two types, either megasporangia that are few in number (approximately 10), each with single megaspore, or many microsporangia, each with 64 microspores.