PREFACE 



There are many problems in the general economy of the ocean and lakes the 

 solution of which requires the aid of the microbiologist. In fact, there are very 

 few questions regarding the science of the sea which can be satisfactorily an- 

 swered without due consideration of bacteria, yeasts, molds, and related organ- 

 isms, and of the chemical and geological processes in which such organisms are 

 involved. 



The role of microorganisms in the carbon, nitrogen, sulfur, and phosphorus 

 cycles in the sea as well as in the general circulation of organic compounds by 

 processes analogous to those in the soil is usually taken for granted. By virtue 

 of their effects upon plant nutrients, the microorganisms with which the micro- 

 biologist is concerned influence the productivity of the sea. Many marine 

 microbes associated with aquatic plants and animals are parasitic while others 

 are beneficial in various ways. The distribution of oxygen and carbon dioxide 

 in water is influenced by microbial activity. Microorganisms are the principal 

 dynamic agencies which influence the hydrogen-ion concentration and oxida- 

 tion-reduction potential of natural bodies of water and of the underlying bottom 

 deposits. There are several ways in which microbial activities affect the 

 diagenesis of sedimentary materials, including protopetroleum. There are 

 doubtless questions of variations in the interfacial and surface tension of water, 

 colloidal state, or conditions affecting the penetration of sunlight for which 

 microorganisms must be held in part responsible. 



Microbiology thus occupies a logical and prominent position as an integral 

 marine science. Besides contributing to a fundamental study of the sea, its in- 

 habitants, its constituents, its boundaries, and its relation to man, the marine 

 microbiologist is confronted by several practical problems such as the role of 

 microorganisms in the spoilage of fish and other marine products, the fouling of 

 ships' bottoms, and the deterioration of fish nets, cork floats, ropes, and wooden 

 structures exposed to water. Likewise the marine microbiologist is in a position 

 to contribute to sanitary science and to the pure science of bacteriology. 



The hydrobacteriological investigations of the pioneers, including B. Fischer, 

 Frankland, Houston, and Jordan, were concerned primarily with the dis- 

 tribution and behavior of bacteria in water. Since the turn of the century more 

 and more attention has been focussed upon a study of the factors which influ- 

 ence the survival of coliform or other adventitious organisms of hygienic inter- 

 est. However, a handful of scientists have continued to accumulate informa- 

 tion on the distribution, characteristics, biochemical activities, and hydro- 

 biological importance of microorganisms indigenous to aquatic environments. 

 Special methodology has progressed apace. As a result, marine microbiology 

 has become a specialized field of research which is world-wide in scope. 



In this volume an attempt has been made to summarize and correlate the 

 extensive literature on the subject, with particular reference to the importance 

 of bacteria and allied microorganisms as biochemical, geological, and hydro- 

 biological agents. Although conditions in the sea serve as the central theme, 

 frequent reference is made to observations in inland bodies of water, both fresh 

 and saline. It is possible that common elements in the evolutionary histories 



