Plants that have no conductive (vascular) tissue are referred to as bryophytes. They include mosses, hornworts and liverworts, all of which reproduce with spores and do not form flowers or seeds. Liverworts are common in the tropics, but certain species are plentiful in New England. They are divided into two groups: flat, leafless thallus liverworts and leafy liverworts, which typically resemble flattened moss. You can easily confuse leafy liverworts with mosses but there are microscopic differences between the two. If you examine them under a microscope, you will find that leafy liverworts have leaves that are arranged in two or three rows while the leaves in mosses are spirally arranged. Liverworts of the Frullania genus, such as the liverwort pictured in this post, are classified as leafy liverworts. They typically have a reddish-brown color and attach themselves to a tree or other plant, obtaining moisture and nutrients from the air.
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