THE BEHAVIOR OF CERTAIN MICRO-ORGANISMS IN BRINE. 



By George James Peirce. 



The number of organisms, plants and animals known to live under what are com- 

 monly supposed to be fatal conditions is a surprisingly long and increasing one. Illustra- 

 tions more or less generally known include the molds of various sorts which seem to thrive 

 vegetatively, if not reproducing themselves otherwise, on solutions of strychnine, formaline, 

 and carbolic acid; the insects in the seepages of oil wells and asphaltum; the organisms in 

 hot and cold waters. In all of these, however, conditions are fairly stable, and the organ- 

 isms, once able to adjust themselves to the unusual factor or factors of the environment, 

 can continue to survive by maintaining this adjustment. It is still harder to understand 

 how organisms can continue to readjust themselves to conditions which change greatly 

 from those ordinarily called favorable to those fatal, and vice versa. Mild examples of this 

 sort are afforded by those craft regularly plying between salt and fresh water, on the 

 bottom of which algae and other organisms seem to thrive despite the range of the moving 

 environment. Osterhout, 1 for example, describes the red, brown, green, and blue-green 

 algae thriving on the bottoms of the steamers which daily make the trip between San 

 Francisco (with sea-water of approximately 3 per cent salt-content) and Stockton (with 

 fresh water). In these instances, however, the range of environment is comparatively 

 short, but it is also run through in a very short time. 



Annual ranges of temperature between the favorable and the fatal are general and we 

 take more or less for granted the means of adjustment to them possessed by plants and 

 animals. In certain parts of the world annual ranges of moisture of similar extent are 

 well known and more or less understood, but annual changes of an extreme sort in other 

 factors of the environment are less common. Where salt is made from sea-water extreme 

 changes in the salt-content of water regularly occur. In the salt works on the shores of 

 the Bay of San Francisco the changes are annual. In spite of the extreme annual range 

 from rain-diluted sea-water to brine from which common salt crystallizes, there are many 

 organisms which live in the salterns. Some of these organisms will be considered in the 

 following pages, but we should first ascertain the conditions under which they exist. 



LOCATION. 

 Lying between two ranges of mountains which run parallel with the coast-line of 

 middle California is the Bay of San Francisco. It possesses an area of nearly 500 square 

 miles. Nearly midway of its north and south extent this great sheet of water communi- 

 cates with the Pacific Ocean through the Golden Gate, a narrow passage between two 

 mountains of the outer coast range. From the east it receives the drainage waters of the 

 great central plain of California in the San Joaquin and Sacramento River systems, while 

 small streams running down the slopes which bound the valley flow into the bay at various 

 points during perhaps half the year. The shores of the bay are mainly flat. There are 

 extensive areas of undrained marsh where plants of various sorts are contributing to land 

 formation. Other areas are fairly dry throughout the dry season and covered with a mat 

 of low herbs, the roots of which bind the clayey soil into a firm turf. In this, as in other 

 "adobe" soils, cracks open on the surface during the dry season. These long and irregular 



1 Osterhout, W. J. V.: The resistance of certain marine algae to change in osmotic pressure and temperature. 

 Univ. Calif. Publ., Botany, n, 227-8, 1906. 



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