Section 1: Deals with cylindrical, delegate genera of the Placoderonae. these are Penium, Closterium, Spinoclosterism, Docidium, Plevrotaenium, taiploceras and Tetmemorus. Descriptions of new species and varieties as well as previously identified ones are presented, along with synonymies. Each form is illustrated. Forthcoming sections of Part 2 will consider other genera of the Placoderms. Section 2: Contains consummate for the genera Euastrum Ehrenberg 1832 and Micrasterias Agaroh 1827. Section 3: Present the genera Actinotaenium, Cosmarium, Cosmocladium and Oocardium. Section 4: Includes Spinoecosmarium, Arthro-desmus, Xanthidium and Staurastrum. Section 5: Deals with filamentous genera.
