MICRO-ORGANISMS OX CAPTURED FLIES 289 



The bacteria were roniovetl in th(> nnlitiury manner and were sub-cultured, 

 plated out and identitied as follows : 

 Micrococcus ureae 

 Bacillus snhtilis ... 

 Bacillus coll commwie ... 

 Sarcina lutea 

 Bacilli stained by Gram 

 Bacilli not stained by (Jram.. 



Experiment No, 2. 



A fly was caught at 11.30 a.m. on May 4th out of doors on Central Hill, 

 Norwood, London, and was allowed to walk over nutrient agar-agar at 

 12 o'clock noon. 



May 4th, 6 p.m. Colonies were plainly forming. 

 „ 5th, 10 a.m. 13 colonies of bacteria and 6 colonies of fungi. 

 „ 6th, 10 a.m. 21 „ „ 7 „ 



„ 7th, 10 a.m. 39 „ „ 7 „ 



„ 8th, 10 a.m. 46 „ „ 7 „ 



That is, in 94 hours, 46 colonies of bacteria and 7 colonies of fungi were 

 obtained from thi.s fly No. 2. The fungi were identified as follows: 



2 colonies of Macrosporium .sp. 



3 „ Penicillium glaucum 



1 colony of Cladosporium herharum 



1 „ Fusarium roseum 



The bacteria after being sub-cultured and plated out were identified as: 

 Bacillus tumesceiis ... ... 18 colonies 



Micrococcus pyogenes aureus ... 9 „ 



Sarcina lutea 2 „ 



Sarcina ventriculi ... ... 1 colony 



Bacillus amylohacter ... ... 4 colonies 



Acid-fast bacillus ... ... 1 colony 



Bacilli stained by Gram ... 4 colonies 



Bacilli not stained by Gram ... 7 „ 



Experiment No. 3. 



This experiment was perhaps the most interesting of the three as the fly 

 was captured at 10.30 a.m. on May 4th on a dust-bin (Norwood, London), a 

 situation in which flies are frequently found. It was allowed to walk over 

 the surface of nutrient agar-agar. 



May 4th, 6 p.m. Signs of colonies observed. 

 „ 5th, 10 a.m. 18 colonies of bacteria and 7 colonies of fungi. 

 „ 6th, 10 a.m. 58 „ „ 9 „ 



„ 7th, 10 a.m. 113 „ „ 10 „ 



„ 8th, 10 a.m. 116 „ „ 10 „ 



H. H.-F. 19 



