83 



rely only upon the surrounding structures being stained and the spore, 

 left untouched, appearing as a clear structure. 



The number of bees examined from each stock was, on an average, 

 about eight. Where more than eight bees were available from a stock, then 

 these were also examined. 



The amount of infection was reported as slight, heavy, or very heavy, 

 according to the number of spores found. 



Where young stages were found, these were recorded as such, but it 

 was rare to find a heavy young stage infection without the presence of a 

 fairly heavy infection with spores. • 



The routine here described was that followed by Dr Innes in the 

 laboratory, in all cases of bees which were sent for Nosema diagnosis 

 from the Lewis stocks, from apiaries on Deeside, and several other 

 districts. Examinations of bees for Nosema by the other workers was 

 mostly, though not exclusively, confined to the searching for spores. These 

 were obtained by examining bees in the fresh state and by the pulping 

 method described later. Miss Simpson and Dr Eennie also prepared a 

 number of sections of the alimentary canals of iVbsema-infected bees 

 (apparently normal in behaviour), of Isle of Wight diseased bees, and of 

 healthy bees, some of which are utilised in illustration of the present work. 



Diagnosis of Nosema Infection in Dead Bees. 



Graham-Smith, Fantham and Porter, in their report upon Nosema as the 

 cause of Isle of Wight disease, express the opinion that dead bees are 

 unsuitable for Nosema diagnosis (p. 41). This opinion is reflected in the 

 Board of Agriculture Leaflet, where it is stated that " it is not possible as 

 a rule to express any opinion from an examination of dead bees." Leaving 

 out of the question altogether the problem of Isle of Wight disease, and 

 considering only that of Nosema, infection, this statement has not been 

 borne out by our experience. Undoubtedly, the most reliable means of 

 diagnosis of Nosema infection is the recognition of the spores, and our 

 experience has been that these are recoverable from bees at least as long as 

 seven months after their death. We have in our possession at the present time 

 (January 1916), a number of dead bees which were artificially infected 

 with Nosema early in June 1915, in which we are still able to obtain spores, 

 not only from numbers pulped together, but readily from individual bees. 



Graham-Smith, Fantham and Porter are of opinion that spores are not 

 often formed in the warmer months of the year. They state : " Undoubtedly 



