NOSEMA-DISEASE. 



31 



Table VII shows that Nosema apis in a honey suspension was 

 destroyed by heating for 10 minutes at a temperature between 136° F. 

 (58° C.) and 140° F. (60° C), the death point being about 138° F. 

 (59° C). 



RESISTANCE OF NOSEMA APIS TO DRYING. 



In experiments relative to the effect of drying on Nosema apis, 

 stomachs from Nosema-infected bees were crushed, and the crushed 

 tissues were smeared on slides to the extent of a thin layer. The 

 slides were placed in incubator, room, outdoor, and refrigerator tem- 

 peratures, respectively. At different intervals after the preparation 

 of the smears an aqueous suspension was made, germs from two slides 

 representing the material from 5 to 20 bees being used. This was 

 added to sirup and fed to a healthy colony. Whether or not the 

 parasite had been destroyed was determined by the presence or 

 absence of Nosema-infection in the colony following the inoculation 

 with the sirup. 



NOSEMA APIS DRYING AT INCUBATOR TEMPERATURE. 



In Table VIII are summarized the experiments, together with the 

 results obtained, in which the Nosema material was allowed to dry at 

 incubator temperature. 



Table VIII. — Resistance of Nosema apis to drying at incubator temperature. 



Date of inoculation. 



July 

 July 

 Oct. 

 July 

 July 

 Sept 

 Nov 

 / Sept 

 Oct. 

 July 

 May 

 July 



30,1915. 



14,1916. 



5,1914.. 



21,1915. 



29,1916. 

 11, 1914 

 2,1914.. 



. 29, 1914 



16,1914. 



9,1915.. 



24, 1915 . 



9,1915.. 



Period of drying. 



Months. 

 

 

 

 

 

 

 

 

 

 2 

 7 



Days. 



Results of inoculation. 



Nosema infection produced. 



Do. 



Do. 



Do. 

 No infection produced. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



From Table VIII it wiU be seen that Nosema apis drying at incu- 

 bator temperature was destroyed in from 15 to 21 days, that is, 

 during the third week. 



NOSEMA APIS DRYING AT ROOM TEMPERATURE. 



In Table IX are summarized experiments in which the drying of 

 Nosema apis took place at room temperature. 



