... consist of single cells, or of filamentous or other groups of cells, according as the divisions are completed at once or not. While some unicellular forms are less than 1 [micron] (.001 mm.) in diameter, others have cells measuring 4 [micron] or 5 [micron] or even 7 [micron] or 8 [micron], in thickness, while the length may vary from that of the diameter to many times that ... — Encyclopaedia Britannica, 11th Edition, Volume 3, Part 1, Slice 2 - "Baconthorpe" to "Bankruptcy" • Various Read full book for free!