SCIENCE 



[N.S. Vol. XXV. No. 647 



and is in general use by authorities in text- 

 books on bacteriology. 



The term 'degeneration forms' is, how- 

 ever, less definitely defined in the text- 

 books. The Standard Dictionary defines 

 degenerate, ' to become worse or inferior; 

 decline ia character, qualities, or excel- 

 lence, as from the normal or primitive con- 

 dition or from a type of standard; dete- 

 riorate.' According to this definition, the 

 term 'degenerate forms' should be reserved 

 for those organisms that had reached the 

 normal stature and subsequently mani- 

 fested the effects of degenerative influ- 

 ences. These effects are seen principally 

 as vacuolation, granulation, and fragmen- 

 tation of the protoplasm in organisms of 

 normal size and shape. 

 The Production of Indol in Proteid^free 

 Media: M. X. Sullivan, Brown Uni- 

 versity, Providence, R. I. 

 Several years ago, I found that B. coli 

 communis would grow well on non-proteid 

 media. At that time no tests were made to 

 determine whether or not iadol and skatol 

 were produced on these media. Under the 

 pressure of other work the experiments on 

 B. coli were not continued. Recently, 

 however, my attention was again directed 

 to the metabolism of B. coli by L. F. 

 Rettger's article ' Studies on Putrefaction,' 

 Jour, of Biol. Chem., '06, Vol. II., p. 71. 

 Accordingly solutions of non-proteid media 

 were made and inoculated with a pure 

 culture of an indol-forming variety of B. 

 coli in order to determine whether or not 

 this bacillus could produce indol in simple 

 media. 



The culture medium on which the pres- 

 ent conclusions are based consisted of 



Asparagin 0.2 grm. 



Mannite 0.2 



NaCl 0.02 



MgSO, 0.01 



CaClj 0.02 



KjHPO, r 0.2 



H,0 100 c.c. 



This medium was made slightly alkaline 

 to litmus and divided into two portions of 

 2,000 c.c. each: flask {A) and flask [{B) re- 

 spectively. To (B) was added CaCOg to 

 take up whatever free acid might be 

 formed. Both portions were then steril- 

 ized and inoculated with B. coli. 



In periods varying from five to ten days 

 the contents of ,(J.) and (B) were analyzed 

 for indol and skatol. In no case was indol 

 or skatol found, either in the distillate or 

 in the original solution. An inoculation 

 from the non-proteid medium containing 

 B. coli to bouillon produced in a few days 

 a good growth with the formation of indol. 



From these experiments it would seem 

 that indol is not formed synthetically, but 

 in ordinary culture media is a result of the 

 decomposition of the albuminous material 

 present. Long-contiaued growth of B. coli 

 on a non-proteid medium I believe will 

 give a test for indol, since the death of 

 many micro-organisms will leave an albu- 

 minous material in the medium. 



The Sterilization, of Sevmge-Filter Efflu- 

 ents: Earle B. Phelps. 

 The development of the modem, rapid 

 processes for the purification of sewage has 

 led to a new conception of the functions of 

 a sewage-disposal plant, in which concep- 

 tion the removal of bacteria finds but small 

 consideration. The cost of obtaining high 

 bacterial efficiency, by means of sand filtra- 

 tion, is so much greater than the cost of 

 producing an effluent which is non-putres- 

 cible, though germ-laden, that the former 

 can not as a rule be employed in the treat- 

 ment of the sewage of large cities, unless 

 bacterial purification is imperative. In 

 certain cases, as for example where im- 

 portant shell-fish industries are threatened, 

 it does become necessary to consider bac- 

 terial as well as chemical purification. As 

 an alternative to treatment on sand, either 

 as the chief, or as a supplementary process. 



