4o6 Louise Hoyt Gregory 



B13 and B14 were placed in a solution containing ten drops of 

 medium, and one drop of medium plus pancreatin. B16 and B15 

 were put in a solution containing ^ plain medium and | medium 

 plus pancreatin. This last solution proved to be too strong, and 

 both individuals died after four days. These lines were filled in 

 from B13 and B14, both of which were doing well. The variations 

 in this series are abrupt, and the entire set died at the end of the 

 17th period. 



Individuals treated with beef extract seemed to have their 

 vitality increased to a greater extent than those treated with any 

 of the other stimulants. At the I2th period four lines were started 

 from the main culture. These were put in a solution of beef 

 extract (fresh pieces of beef were put in cold water and brought 

 to a boil, then allowed to cool). B17 was treated two days, B18 

 for three days, and B19 and B20 for four days, the medium being 

 changed on the third day to fresh extract. On April 20, at the 

 end of the i6th period, the vitality seemed to be decreasing, and 

 B19 and B20 were stimulated, B17 and B18 being left untouched. 

 The result is evident, B17 and B18 died at the end of the 20th 

 period, while B19 and B20 lived fifty days longer, dying out on the 

 25th period, at a time when there was great mortality among all 

 the lines. This period followed one of high rate of division 

 caused by an unusual rise in temperature. 



The experiments with alcohol were started on June 23, for 

 which four lines, B25, 26, 27 and 28, were used. One drop of a 

 solution of 50CC. HoO +1 cc. 100 per cent alcohol was added to the 

 medium in which B25 and B26 were living, and two drops of the 

 above solution were added to the medium in which B27 and B28 

 were living. This was changed each day. B25 died in four days, 

 the line was filled in from the stock B26. B28 died in three days, 

 and the line was filled from the stock of B27, and all four lines were 

 then treated with two drops of the alcohol solution. This treat- 

 ment had no stimulating influence, and on July 8, the entire cul- 

 ture died, having lived 16 days. A second culture was started 

 October i, and died on October 17, this also having lived 16 days. 



The results of the first series of experiments may be briefly 

 stated at this point: 



