G. W. Bullamore 01 
what may have been a bacterial disease was being investigated as the Isle of 
Wight disease 1 . 
Tinsley (1918), in a bulletin issued by the West of Scotland College of 
Agriculture, states that he succeeded in infecting healthy bees with Isle of 
Wight disease by feeding them with sugar syrup in which the liquid contents 
of the intestines of sick bees had been incorporated. In one of Dr Rennie’s 
earlier experiments (1919 a) Nosema spores in candy were fed to healthy bees 
in May. Crawling without Nosema was recorded as being present in June 
and the bees were found dead the following January. In 1915 also, pulped 
diseased bees were fed in honey to a stock on June 28th. The stock swarmed 
and both lots showed crawling in October and died out. The nearest bees 
were two miles away and remained healthy (Anderson and Rennie, 1916). 
We assume that the Nosema spores were obtained from sick bees and that 
bacteria and other organisms were therefore unavoidably present in the 
candy. The results obtained by Dr Rennie may thus have been due to the 
organism that was present in the cases recorded by Tinsley. That organism 
is unknown, but the results suggest that it was situated in the alimentary 
canal. 
V. Conclusions. 
Acarine disease appears to be less virulent than the disease which swept 
across the Isle of Wight in the early years of this century. That the mite was 
causing damage at the same time is very probable but the investigations 
were centred on the acute and virulent disease. 
It may be that most of the stocks affected with mites, but showing no 
symptoms of disease, die out sooner or later. But this does not demonstrate 
the existence of a new disease. It merely emphasises the soundness of the 
older system of beekeeping which considered it undesirable to retain any 
stock after the third season, the less desirable colonies being sulphured at an 
earlier period. 
Although it may not be the cause of the Isle of Wight disease the dis¬ 
covery of the mite is of economic importance, revealing, as it does, one of the 
causes of the failure of modern beekeeping. Ever since the introduction of 
the “humane” system which saved the redundant bees and distributed them 
as “driven bees” throughout the length and breadth of the land, there has 
been a steady increase in disease which has helped to render the industry of 
honey production an unprofitable one. Before the rise of the Isle of Wight 
epidemic the losses were attributed usually to foul brood, although there was 
1 The difficulty in classifying bee disease by symptoms is well shown by the following instance. 
While the work on Nosema in its relationship to Tsle of Wight disease was being carried out 
at Cambridge there ensued a heavy mortality of humble-bees which was found to be associated 
with the presence in the Malpighian tubes of a protozoon closely resembling Nosema. In the 
year immediately past a similar mortality has been noticed in humble-bees, but the protozoon 
could not be found. The organism accompanying the mortality in 1921 was a nematode worm 
Sphaerularia bomhi which undergoes development in the body cavity of the bee and eventuall}' 
gives rise to huge numbers of larvae. Tn both years, the symptom of the trouble was inability to fly. 
