Abstract
Winogradsky, 1 Cholodny, 2 and Conn 3 have shown that a different bacteriological picture is presented when the microorganisms which attach themselves to glass slides incubated in the soil are observed directly, than when the same soil is studied microbiolog-ically by the conventional cultural methods. Henrici 4 studied freshwater bacteria by such a direct microscopic method. We used a somewhat similar procedure to study marine bacteria on the coast of southern California. Our experiments were designed to supplement the work of Coe and Allen (Coe 5 ) at the Scripps Institution of Oceanography on “fouling organisms” so destructive to navigation equipment and other marine structures (Visscher 6 ).
Standard slides, bacteriologically clean, were submerged off the end of the Institution pier, and after one to 7 days' submergence the slides were taken with aseptic precautions to the laboratory for examination. Results indicate that attachment of bacteria and, to a lesser extent, diatoms and actinomycetes, usually precedes the attachment of barnacles, hydroids, bryozoa, and other “fouling organisms” by several hours or even days.
Many forms of bacteria which have not been recovered by concurrently plating samples of sea water on culture media have been observed directly on these slides. However, not all marine bacteria attach themselves to submerged glass slides.
Seventy-three pure cultures isolated from the sea and differing morphologically or physiologically were tested under controlled conditions for their attachment propensities. The bacteria were inoculated into wide-mouth bottles containing nutrient sea water. Sterile glass slides were inserted vertically. After 2 days' incubation at 25 °C. the slides were examined.
Get full access to this article
View all access options for this article.