LABOEATORY AND GREENHOUSE STUDIES. 



71 



Table IX.- 



pi 



onid of (/(IS (in mm.) produced by various cultures in 1 per cent peptone 

 '.us 1 per cent cane sugar at 22° 0., experiments 1 and 2. 



Culture. 



Coconut 1 . . 

 Coconut 1 a 

 Coconut 2 . . 

 Coconut 2 a 

 Coconut 3 . . 

 Coconut 3 a 

 Coconut 4 . . 

 Coconut 4 a 

 Coconut 5 . . 

 Coconut 5 a 

 Coconut () . . 

 Coconut 6 a 



Exp. 1: Dec. 8-28, 1909. 



1 

 day. 



0) 



0) 

 ( 



{*) 



2 

 days. 



10 

 days. 



40 



70 



13 



13 



















15 



17 











20 

 days. 



50 

 55 

 12 

 15 

 30 



30 











20 



15 



(^) 

 (?) 



Exp. 2: Feb. 4-20, 1010. 



1 

 day. 



3 



days. 



13 



11 



"6 







"6 



7 

 days. 



40 



10 

 "6 







'io 



"6 



10 

 days. 



50 







is 



'6 



14 

 days. 



59 



(^) 







is 

 "6 



1 Tiny bubbles. 



2 One large bubble. 



3 Various tubes of this culture previously produced gas in cane sugar. 

 < Small amount. 



Here, as in the case of dextrose and lactose, is a failure on the part 

 of certain cultures to produce gas. Coconut Nos. 3, 4, and 6 seem to 

 have less power in this direction than the other cultures. In dextrose 

 and lactose media these cultures sometimes failed and sometimes did 

 not. In the only experiments carried out with cane sugar they failed. 



GROWTH IN NITRATE BOUILLON. 



Cultures were made in nitrate bouillon, and within two days, tests 

 for nitrites with starch, potassium iodid, and sulphuric acid showed 

 the presence of nitrites, thus mdicating the abiHty of the organism to 

 reduce the nitrates. This test has been repeated many times and in 

 no case did any of the cultures fail to give a good reaction. 



COLOR PRODUCTION. 



The coconut organism does not produce any pigment. On plain 

 agar the growth is white in direct light. Wliere the growth is thin on 

 agar plates the colonies in transmitted light are bluish. On potato 

 cylinders there may be a slight yellow color to the growth. On media 

 containing neutral red the growth is pink, eventually fading to 

 orange yellow, but that is undoubtedly due to the presence of the 

 neutral red. On Kashida's litmus-lactose agar (p. 119) the colonies are 

 fu'st slate blue, then red. On Endo's fuchsin agar (p. 88) the growth 

 is bright red, or, at a certain stage, white in direct light and irides- 

 cent in transmitted light. All of these colors, however, are doubtless 

 due to reactions in the medium and are not direct products of the 

 bacterial growth. 



228 



