Algological Investigations in Mammoth Cave, KentuckyWith plate 104 (1) and one figure in the text IntroductionBiospeleology in the United States is still in its early descriptive period and though the situation has greatly improved since 1931 when Bolivar and Jeannel could make the following statement:" ... les naturalistes americaines n'ont enterpris aucune etude serieuse de la faune de l'immense domaine souterraine qui s'offre a leurs investigations. On chercherait en vain dans les collections des Musees un seul cavernicole dont la capture date du XXc siecle !," still not a single article deals with American cave floras exclusively.Scientific inquiry into the microbiological-botanical investigations of the flora of the closed ecological system of caves has been given scant attention especially in comparison with the zoological works conducted in these subtel'l'anean habitats. This statement especially holds true for the cavernicole plants of the caves of the United States. Such studies had been initiated already at the end of the last century in European caves and even in America in the early work of Call (1897) 15 fungi are enumerated which were identified from Mammoth Cave in Kentucky. However, due probably to Call's interpretation that all of these fungi are accidental inhabitants of the cave, their presence possibly did not give rise to any special interest which would have furthered the continuation of similar investigations. It is by now an established fact that algae do occur in the total darkness of caves, often in considerable quantities, and it therefore seemed necessary to conduct algalogical investigations into one of the largest caves on the North American continent, the Mammoth Cave of Kentucky. The algal flora of this cave differs considerably from those found in caves 1) Biological Institute, l\latthew Maury Hesearch Center, Long Island, N.Y. Present Address: '150!. Hilltop Drive, Tallahassee, Florida. 2) This paper represents a portion of a thesis submitted to The Free Protestant Episcopal University, England, in partial fulfillment of the requirements for a Doctor of Philosophy degr'ee in l\Iicrobiology. 492Speleology I Jones on the European continent, and a comparison between these geographically isolated habitats will be discussed.Very few metazoans and only a limited number of microorganisms have been able to adapt to an eternally lightless environment in which food must be either manufactured in situ by chemosynthetic autotrophs or carried in from the outside. Deep caves provide an essentially isolated thermal environment, in which the most important limiting factors are light, food and vapor pressure deficit.Caves have received slight attention in the past partially due to the fact that no economic usc has been expected from them and also because they arc extremely difficult to study. Even the genesis of the limestone cave is obscure. Complications in the biological research of United States caves arc due to a lack of prior taxonomic work and also to the physical problems encountered i...

No abstract