In this article we will discuss about the external morphology of vaucheria.
1. Plant body is tubular or cylindrical and irregularly branched (Fig. 30).
2. Terrestrial species are attached to the substratum by rhizoids.
3. Plant body is aseptate and multinucleate (coenocytic). However, some septa formation is observed at the base of reproductive organs.
4. Wall of the filament is thin, elastic and consists of an outer layer of pectose and an inner layer of cellulose.
5. In the cytoplasm are present many chloroplasts and nuclei.
6. Chloroplasts are oval or discoid in shape and present in the form of a layer.
7. Next to the chloroplasts is a layer of nuclei.
8. Pyrenoids are absent.
9. Large number of oil droplets make the reserve food material of the thallus.
10. A large central vacuole is present in the centre of the thallus, which is the characteristic feature of the order.