NOSBMA-DISEASE. 



33 



, It is learned from the results recorded in Table XI that Nosema 

 ^pis drying at refrigerator temperature remained 'virulent i for seven 

 aaonths but that no disease was produced following inoculation with 

 the material after seven and one-haJf months d?^ying. 

 ' From the residts obtained in the experiments relative to the resist- 

 ance of iVbSema apis to dtying, given in Tfeibles VIII-XI, it will be 

 abserved thtit ' the period the parasite remaihed aliv^, or at least 

 ^virulent, varied, depending Upbh the environment of the gerhi. The 

 shortest period for the destruction of spores was obtained under 

 Jncubator conditions, while the longest period pcourred under refrig- 

 jiBrator conditions. The death probably was not due to the drying 

 ^alone but to a combination of factors of which drying was an impor- 

 tant one. 



RESISTANCE OF NOSEMA APIS TO FERMENTATION. 



Experiments have been miade to obtain data relative to the resist- 

 ance of Nosema apis to ferinentative processes. In conducting the 

 , experiments suspensions of the crushed stomachs from Nosema- 

 -infected bees were made in a 10 per cent sugar (saccharose) solution 

 *and in a 20 per cent hdney solution. These solutions were distributed 

 "in test tubes. Each tube contained infectious material equal to that 

 ipresent in the stomachs of from 5 to 10 infected bees. To each sus- 

 pension was added a bit of soil to inoculate it further. Suspensions 

 were allowed to ferment at incubator, room, outdoor, and refrigerator 

 "temperatiires, respectively. At intervals reckoned in days the fer- 

 menting suspension from a single tube was traiisferred to about one- 

 half pint of sugar sirup and fed to a cplony free from the infection. 

 The results were then noted. 



FERMENTATION AT INCUBATOR TEMPERATURE. 



In Table XII are summarized some of the results that were obtained 

 when a suspension of Noseirw, apis in a 20 per cent aqueous solution 

 of honey was allowed to ferpient ^tincubatpr. temperature. 



Table XII. — Re/sistomce of Nosemuf apis to/ermentation in a honey solviim,. 



Date of inoculation. 



Period of 

 fermen- 

 tation. 



Besults of inoculation. 



July 25, 1916. 

 July 26, 1916. 

 I July 27, 1916. 

 July 28, 1915. 

 July 12, 1915. 

 July 15, 1916. 

 July 17, 1916. 



Days. - 



2 

 3 



4 

 6 

 8 

 10 



Nosema infection produced. 



Do. 

 No Infection produced. 



Do. 



Da 



Do. 



Da 



