TWO CILIATA OF GREAT SALT LAKE. 1 

 DEAN A. PACK. 



INTRODUCTION. 



Great Salt Lake is not a body of water without its natural 

 fauna and flora. Its water has not yet reached the point of 

 saturation for sodium chloride. It is not the lake of no life, 

 whose water is thought, by the public in general, to be purified 

 by the abundance of salt in solution. It is a lake that contains 

 probably less than fifty forms of life, some of which are visible 

 to the naked eye. Upon careful microscopic examination of a 

 generous amount of the Great Salt Lake water (23 per cent, 

 salinity) many forms of life are observed. To date there have 

 been seventeen different forms reported; as nine algae, five 

 bacteiia, two protozoans, one crustacean and two fly larvae. 



The plan of work was to study the effect of dilution on Great 

 Salt Lake forms. Out of a number of algae and protozoans, two 

 ciliata were chosen for experimentation. 



MATERIAL. 



The material was collected early in September, 1917, from 

 near the shore of Great Salt Lake in the vicinity of the Salt Air 

 Pavilion and permitted to stand in the laboratory until January, 

 1918. As no water was added to the material, it concentrated 

 to a density of 1.170 at 60 degrees Fahrenheit, by the first of 

 January, 1918, when the first dilutions were started. A good 

 balance between the animal and plant life was established and 

 the cultures retained their clearness through all the different 

 densities from the point of saturation down to the density 1.015 

 (at date). 2 The decaying and milky cultures spoken of by 

 other observers were not encountered. The Aphanothece and 

 some other plants grew and reproduced, in all the different 

 densities from 1.20 to i.oio, thus serving as animal food and 

 giving the cultures their characteristic lake green color. 



1 Contribution from the Zoology Department of the University of Utah. 

 - August i, 1918. 



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