According to Eichler's classification, plant kingdom is divided into two subdivisions cryptogamae and phanerogamae. Cryptogamae has 3 divisions thallophyta, bryophyta and pteridophyta. Thallophyta in turn is divided into 2 classes, algae and fungi. As both these groups have generally undifferentiated plant body (not differentiated into true root, stem and leaves) they are called thallophyta. Also they are non vascular plants. But algae are chlorophyllous and hence show autotrophic mode of nutrition ie can prepare their own food. But fungi are nonchlorophyllous and cannot prepare their own food. So they are heterotrophic in nature.