The New Student's Reference Work/Thallophytes

Thallophytes (thăl′lō-fīts), the lowest of the four great divisions of the plant kingdom. The name means thallus-plants, the thallus being the characteristic plant-body, which is usually prostrate and has no differentiation of nutritive organs, as the roots, stems and leaves of higher plants. All parts of this body are practically alike. There are two great general divisions of the group: (1) Algæ, which contain chlorophyll and hence can manufacture their own food and live independent of any other organisms; and (2) Fungi, which do not contain chlorophyll and hence are dependent upon other organisms for their food. Besides the ordinary algæ and fungi the thallophytes contain many forms which are not classified easily, as slime-moulds, bacteria, diatoms etc. The group is an immense one, and contains the minutest of living forms, as well as some which are very bulky, as some of the seaweeds. Thallophytes are of special interest as representing the beginnings of the plant-kingdom, the group from which all the higher forms have been derived.