SYSTEMATICS OF THE ZYGNEMATACEAE (CHLOROPHYCEAE). III. TRANSEAU COLLECTION OF THE ZYGNEMATACEAE: AN OLD COLLECTION WITH MODERN USES

Edgar Nelson Transeau, botanist‐ecologist‐phycologist, accumulated a worldwide collection of algal specimens for the compilation of a monograph on the algal family Zygnemataceae, published in 1951. Following his death on January 26, 1960 this Collection remained at The Ohio State University, Columbus until 1978 when it was transferred to the University of Arizona, Tucson. A set of glycerine‐preserved specimens on microscope slides is the major item of the Collection with the number of species represented as follows: Spirogyra (138), Mougeotia (52), Zygnema (45), Zygnemopsis (16), Sirogonium (9), Debarya (9), Zygogonium (4), Mougeotiopsis (1) and Entransia (1). All specimens of Pleurodiscus, Sirocladium, Temnogametum and Temnogyra are unidentified. With the Transeau Collection it was demonstrated that an old collection need not be an historical relic, but does have continued usefulness. Potential future use is a powerful justification for maintaining seemingly useless collections whose accumulation often represents the expenditure of untold time, effort and money on the part of many persons and institutions worldwide. Further, as man continues to alter his environment and species are destroyed, collections with long histories become increasingly more valuable. Specimens of the Transeau Collection were subjected to modern techniques, not available earlier, resulting in improved characterization of zygospore‐wall structure by scanning electron microscopy and the determination of nuclear DNA by cytofluorometry.