Traditionally fungi have been regarded as plants. At one time fungi were given the status of a class and together with the class algae formed the division Thallophyta of the Plant Kingdom. The thallophyta were those plants whose bodies could be described as thalli. A thallus is a body, often flat, which is not differentiated into true roots, stem and leaves and lack a true vascular system. A modification of the scheme of classification of fungi proposed by Ainsworth(1973) and adopted by Webster(1980) is outlined below.
Division Myxomycota: They lack cell wall and are quite unusual organisms. Possess either a plasmodium, a mass of naked, multinucleate protoplasm, which feeds by ingesting particulate matter and shows amoeboid movement, or pseudoplasmodium, an aggregation of separate amoeboid cells. Both are of a slimy consistency, hence they are also called “Slime moulds”. It includes three classes.
Division Eumycota: True fungi, all with cell wall. It is customary to recognize five subdivisions under this division.
A. Mastigomycotina: These are zoosporic fungi, many are solely aquatic. Three classes are included in this, each characterized by their distinctive type of zoospores.
B.Zygomycotina: Vegetative body haplophase. Asexual spores are non-motile spores.