496 G. H. DKEW, 



After 72 hours a slight cloud and thick scum, no Nitrite or Nitrate, and very 

 faint Ammonia reaction: 

 The average temperature at which the culture was grown was 29° C. 



3. Sample collected from a spot 6 miles S. of Port Eoyal, wind 

 E.S.E., force 4, high tide (slack). Taken from surface. 1000 c.c. 

 Gran's medium was inoculated with 10 c.c. of the sample. 



After 20 hours a slight cloud developed in the culture ; no Nitrite reaction 



was given. 

 After 27 hours a slight cloud developed in the culture ; faint Nitrite reaction 



was given. 

 After 38 hours a dense cloud developed in the culture ; strong Nitrite and 



faint Ammonia reaction was given. 

 After 48 hours a dense cloud and scum developed in the culture ; strong 



Nitrite and faint Annnonia reaction was given. 

 After 63 hours a dense cloud and scum developed in the culture ; moderate 



Nitrite and faint Ammonia reaction Avas given. 

 After 72 hours a moderate cloud, scum, and bubbles developed in the culture ; 



very slight Nitrite and faint Ammonia reaction was given. 

 After 86 hours a moderate cloud and scum, no Nitrite or Nitrate and very 



faint Ammonia reaction. 

 The average temperatura at which the culture was grown was 29° C. 



4. Sample taken from surface water of the large mangrove swamp 

 lying N.W. of Port Henderson. 1000 c.c. of Gran's medium inoculated 

 with 10 c.c. of sample. 



After 20 hours no cloud or Nitrite reaction. 



After 24 hours slight cloud and slight Nitrite reaction. 



After 40 hours strong cloud and scum, strong Nitrite and slight Ammonia 



reaction. 

 After 75 hours cloud, scum, and bubbles, no Nitrite or Nitrate and slight 



Ammonia reaction. 

 The average temperature at which the culture was kept was 30° C. 



5. Subculture from Culture (1). 1000 c.c. Gran's medium inoculated 

 with 5 c.c. of culture (1) and kept at a temperature of 10° C. to 12 C. 

 by means of ice. 



After 100 hours the culture was quite clear, and gave no Nitrite reaction. 

 It was then removed from the ice and kept at the room temperature, which 

 averaged 30° C. 



After 107 hours a dense cloud developed in the culture, and strong Nitrite 

 and^faint Ammonia reactions were given. 



