They are named after the reproductive structure located in the cup of the fungus called an ascus. Asci are sacs of 8 spores. There are three types of linchen, fruticose, foliose, and crustose. Lower vascular plants have conducting tissues, unlike bryophytes. These plants are covered with a waxy cuticle that does not allow water to pass through it.
Gas exchange is carried on through stomata, small pores in the plant's surface.
Clubmoss - these are similar to true mosses, except larger.