CULTURAL CHARACTERS OP THE DAISY ORGANISM. H? 



results. This experiment was twice repeated witli the same negative 

 results. 



In 1910 another trial was made inoculating into river water con- 

 taining 2 per cent Witte's peptone and testing after 26 days' growth. 

 This time the results were positive. There was a trace of j)ink before 

 heating, and after 5 minutes in the water bath, at 80° C. there was a 

 decided red about half as deep as that given by those strains of 

 Bacillus coll M'liich are considered to be typical indol producers. 



The indol reaction can not be obtahied at the end of 24 hours, and 

 seldom sooner than the eighth to tenth day. 



TOLERATION OF ACIDS. 



Slight toleration for citric, malic, and acetic acids. For the first tests 

 0.5, 1, and 2 per cent of the first two acids were added to tubes of 

 neutral bouillon. A 7-dav bouillon culture was used for inoculatino- 

 the acid media. In six da3^s there was some cloudiness which was 

 least in the tubes containing 2 per cent acid. This cloudiness had 

 not increased in any case a month after inoculating. 



This test was repeated some years later with 1 per cent citric and 

 malic acid, with negative results. 



Tests were then made in 0.5 per cent citric and also in 0.5 per cent 

 malic acid bouillon ( + 71) \vTith negative results. 



A final test was made in a beef bouillon containing 0.25 per cent 

 citric acid ( + 34), and in another containing 0.25 per cent malic acid 

 ( + 38). In the citrated bouillon of this strength both the old and the 

 new strains of the daisy organism grew. In the malated bouillon 

 only the old strain of the daisy organism grew (but there was only one 

 test — 1 tube). Undoubtedly the clouding observed in the first 

 experiments (1907) should be attributed to chemical precipitates 

 which in such acid solutions are frequently thrown out upon standing 

 and become confusing. 



One additional test was made in July, 1910, into peptonized beef 

 bouillon acidulated to +26 with malic acid. Four tubes were inoc- 

 ulated. On the seventh day there was a bacterial pellicle on each one. 

 The fluid was nearly clear — i. e., there Avas no fine clouding, but it 

 contained strings, filaments, and flocks. The organism used was the 

 newest strain of daisy. 



The tests \nth acetic acid were made in 1911 adding it to both 

 agar and bouillon cultures. Small amounts sterilized the cultures. 



TOLERATION OF SODIUM IIYDROXID. 



Tlie toleration for alkali is slight. Transfers were made to -15, 

 -30, and -45 peptonized beef bouillon from a +15 bomllon culture 

 3 days old. Sixteen days after inoculating there was a slight growth 



213 



