Spermatophyte plants that have unenclosed, "naked seeds": The fifth extant division is the flowering plants, also known as angiosperms or magnoliophytes, the largest and most diverse group of spermatophytes. Angiosperms possess seeds enclosed in a fruit, unlike gymnosperms. In addition to the taxa listed above, the fossil record contains evidence of many extinct taxa of seed plants. The so-called "seed ferns" (Pteridospermae) were one of the earliest successful groups of land plants, and forests dominated by seed ferns were prevalent in the late Paleozoic. "Glossopteris" was the most prominent tree genus in the ancient southern supercontinent of Gondwana during the Permian
Vacuum forming for construction equipment, and railcar interior trim and seat components. Vacuum formers are also often used by hobbyists, for applications such as masks and remote control cars. There are some problems encountered in the vacuum forming process. Absorbed moisture can expand, forming bubbles within the plastic's inner layers. This significantly weakens the plastic. However, this can be solved by drying the plastic for an extended period at high but sub-melting temperature. Webs can form around the mold, which is due to overheating the plastic and so must be carefully monitored. Webbing can also occur when a mold is too large