Jena: Gustav Fischer 1922. Second Edition. 304 pages plus ads. Brown paper covered boards. Bookplate of Dr. Siegwart Hermann on front pastedown with his stamp at head of title page. Also sticker of Prof. Dr. phil. Kolkwitz next to his name on title page. A few pages with corner creases. Small tear to spine panel lower portion and number inked on spine. Still a sound copy. Text in German. Mit 12 zum Teil farbigen und 153 Abbildungen im Text. (With 12 partly colored and 153 illustrations in the text.). Good. Boards. 
"Kolkwitz is known for work with Maximilian Marsson (1845–1909) in the development of the "saprobic system" as a biological determination of water quality and levels of organic waste (pollution) in rivers and streams. Their methodology was a non-chemical analysis that was based on patterns of abundance and distribution of various biological species. They examined the biological patterns of approximately 800 species of water plants and invertebrates in their studies, and produced a saprobic index of four zones defining levels of water quality. The term "polysaprobic" was used for river environments with a large amount of decaying organic matter; "oligosaprobic" described locations with the least amount of organic waste, while alpha- and beta-"mesosaprobic" defined moderately polluted habitats. Later, this index was expanded into nine zones, with "xenosaprobic" being the least polluted and poly-saprobic" having the highest level of waste." (wikipedia) Title translates to: "Plant Physiology: experiments and observations of higher and lower plants including bacteriology and Hydrobiology with plankton customer."
google translation of title: "Plant physiology: experiments and observations on higher and lower plants including bacteriology and hydrobiology with plankton science"