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Keywords from Image Description:
Potamogeton pectinatus . en Potamogeton pectinatus cross section through stem showing numerous air spaces nl Schedefonteinkruid dwarsdoorsnede stengel met veel luchtholten Cite book Potamogetons in Relation to Pond Culture Moore Emmeline Washington DC Government Printing Office Plate XXXVII Creator Emmeline Moore PDUWASHFMIB Institution