Algae World: Phycological Research

These pages contain miscellaneous images and data on meiosis and auxosporulation in diatoms, relating to publications or used for cross reference from other pages.

The cover image (above) is a new photograph (obtained 2013) from a 1925 preparation made by Lothar Geitler of epiphytes on Phragmites from the Grosser Plöner See, Germany. The material was fixed using Schaudinn's solution (containing mercuric chloride) and stained with Heidenhain's iron haematoxylin (Geitler 1927). The stain has faded around the edges of the preparations but remains strong in places. Shown here are paired cells of Cymbella neolanceolata (formerly Cymbella lanceolata) at pachytene of meiosis.

Reference: Geitler, L. (1927). Die Reduktionsteilung und Copulation von Cymbella lanceolata. Archiv für Protistenkunde 58: 465–507.

Records of auxosporulation in natural populations of diatoms

• Spreadsheet and reference list supporting chapter "The ecology of diatom reproduction" by D.G. Mann & M.B. Edlund

Auxosporulation in selected pennate diatoms

• Cymbella neolanceolata: paired cells at zygotene (image stack as video file)
• Cymbella neolanceolata: zygotene nucleus (with image stack)
• Cymbella neolanceolata: synizesis (with image stack)
• Cymbella neolanceolata: light microscope documentation of valve morphology in a population from Blackford Pond
• Cymbella neolanceolata: plasmogamy in a population from Blackford Pond
• Cymbella neolanceolata: meiosis (drawings and photographs made from Geitler's 1925 slide preparations)
• Epithemia gametes and auxospores
  
• Parlibellus protracta: vegetative cells and meiosis
  

David Mann,
Royal Botanic Garden Edinburgh
February, June, July 2013