134 



JOURNAL Of THE I)EPARTMfiNf Of AGRlCULfURfi. 



very distinct. Plates were exposed at four points in the 

 chamber for 5 aud 15 seconds, and these after incubation showed 

 an almost negligible amount of contamination. Five out of the 

 eight plates showed no infection whatsoever, while only two 

 growths of Penicillium italicvm. were obtained. 



" Two plates exposed just outside the chamber door, how- 

 ever, were very heavily infected. The one exposed for 5 seconds 

 showed some 26 bacterial and fungus growths, while that exposed 

 for 15 seconds showed 54 growths. Of these there were two 

 growths of Aspergillus niger, six growths of Penicillium 

 italicuvi, and several other species of Venicilliuiii, some bacteria, 

 and some yeasts. 



" Plates exposed in Parliament Street showed practically 

 nothing. 



" On the whole, therefore, judging from the appearance of 

 the chamber and the condition of the atmosphere as revealed 

 by the culture plates, the state of affairs in Chamber No. 20 

 of the Imperial Cold Storage Company is quite satisfactory. 

 With proper precautions this necessary condition can be 

 maintained, but attention in particular will need to be directed 

 to conditions prevailing outside the chamber, otherwise constant 

 opening and closing of the door will be the means of permitting 

 ingress of this air, and thereby bring about contamination of 

 the chamber. 



" The following table shows the amount and nature of the 

 contamination found : — 



3 p.m., I3th December, 1920. 



Locality. 



Length of 

 Exposure. 



Total 

 Number 



of 

 Colonies. 



Nature of Colonies. 



Centre of chamber 

 Floor level ... 



Far corner 



Floor level ... 

 On step at door 



On pile of fruit boxes 

 3 feet high 



Outside chamber, floor 

 level, near door 



On curb Parliament 

 Street 



5 sec. 



15 sec. 



5 sec. 



15 sec. 



5 sec. 



15 sec. 



5 sec. 



15 sec. 



5 sec. 



15 sec. 

 (fig- 2) 



5 sec. 



15 sec. 



1 mixed colony of P. italicum and Bacteria. 

 Bacterial colony forming centre. 



P. ltd I i cum, 

 4 Yeast. 



4 Bacteria, 1 Hoi'modendron. 



4 /-•. ita/iciiin. Rest other species of Peni- 

 cillium. Certainly no P. digitatum, 



2 A.spergillu.s niger. 5 Yeast. 



4 Bacteria. 1 mixed colony of Penicillium 

 and Bacteria. 



1 mixed colony of Penicillium and yeast. 

 2 P. itaUcwm. Rest I'enicillium other 

 species. Certainly no P. digitatum. 



1 Spluici'oneiaa. 



1 Sterile mycelium. 



