61. DuPage River Organism 



In the early course of the study of the flagellation of the bac- 

 teria in the DuPage river west of Chicago a most unusual organism 

 was observed. In flagella stains directly from the water the 

 organism appeared as a large rod, usually curved, often in a semi- 

 circle, and sometimes straight. From the soma protruded numerous 

 spines, much like toothpicks stuck into a wiener. A typical or- 

 ganism is illustrated in Fig, 68f. Typical flagella were never seen 

 on these organisms and their bacterial nature was questioned. 

 After considerable effort the organisms were isolated in pure cul- 

 ture and were found to be flagellated with predominantly polar 

 monotrichous flagella. The flagella are typically very long with 

 relatively short wavelength, averaging 1.37 microns. To date the 

 organism in pure culture has not developed the spines so char- 

 acteristic of the organism in the river water. The identity of the 

 flagellated and the spined forms was established by the observa- 

 tion of spined forms with the typical flagella in the original enrich- 

 ment cultures made by adding small amounts of various nutrients 

 to the river water. Only in these mixed cultures of bacteria, pro- 

 tozoa, and algae have the organisms been seen with both spines 

 and flagella on the same individual. The organisms vary greatly 

 in size and are typically capsulated. In certain media and under 

 certain cultural conditions branching forms may be seen. What 

 is the nature and function of the spines remains to be determined. 



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