NOSEMA-DISEASE. 53 
without the hive." They believed that the condition had been 
endemic in parts of England for many years, and shared with 
Graham-Smith the belief that a large amount of the losses among 
adult bees ascribed to it is due to Nosema infection. 
From the facts at hand it is not possible to state whether the Isle 
of Wight disease and Nosema-disease are One and the same disorder. 
Studies made on the Isle of Wight disease by English workers will 
most likely result in revealing further valuable facts concerning it 
(Anderson and Rennie, 1916). The writer examined one sample of 
adult bees from England taken from a colony suffering from Isle of 
Wight disease. No spores of Nosema apis were found in the sample. 
The results of the examination naturally prove nothing regarding 
the disease. 
For the present the American beekeeper should bear in mind that 
when Nosema-disease is given as the diagnosis, a condition having 
the destructiveness described for the Isle of Wight disease is not 
meant. 
OTHER DISEASES OF ADULT BEES. 
It is quite probable that other diseases of adult bees than those 
referred to here exist. If so, they have not yet been sufficiently 
studied to make their recognition possible, at least by laboratory 
methods. Such disorders could be differentiated from Nosema- 
disease by the absence in them of Nosema apis. As Nosema infection 
is very widely distributed among bees, the fact must always be 
borne in mind that Nosema infection may occur in a colony together 
with other bee diseases and be of secondary importance. This 
caution should never be overlooked. 
PROGNOSIS IN NOSEMA-DISEASE. 
The prognosis in Nosema-disease varies markedly and is dependent 
upon the conditions present. Of these conditions the percentage of 
Nosema-infected bees in the colony, the strength of the colony, the 
season of the year, and the environment of the apiary are among the 
more important factors which determine the outcome of the disease. 
The percentage of Nosema-infected bees in the colony may be very 
small, much less than 1 per cent, or it may be very large, reaching 
practically 100 per cent. Between these limits all degrees of infec- 
tion are encountered, the prognosis in each instance being different. 
As a rule colonies which in the spring of the year show less than 
10 per cent of Nosema-infected bees gain in strength and the losses 
are not detected. This is often true also in cases where the infection 
is somewhat greater than 10 per cent. When the number of infected 
bees approaches 50 per cent the colonies become noticeably weakened 
and in many instances death takes place. When more than 50 per 
