Isle of Wight Disease in Hive Bees. 45 



6. Pulped 27 chyle- stomachs of Welsh driven bees, which were hived 

 to-day in Desswood apiary (29th September 1915), and examined twelve 

 drops for Nosema. Result : Negative. 



Numerous further tests of this nature have been made, and in every case 

 where Nosema was known from previous experience to be present in the 

 collection from which the bees were taken, Nosema spores were found. 



As early as 1913 we had become doubtful of the conclusion that Nosema 

 apis stood in direct causal relation to Isle of Wight disease. From February 

 of that year we regularly examined bees for Nosema spores, especially any 

 that crawled or seemed sickly. We found such spores very frequently, 

 particularly in old bees and not necessarily in association with unusual 

 mortality in a stock. We have found bees with a heavy spore infection able 

 to fly perfectly and even to carry loads of pollen and nectar. We have had 

 under observation for three years, 1913-1915, a stock of Ligurians, G9 (Mcolson 

 Apiary), which has stood in proximity to several of the forementioned stocks 

 throughout their periods of crawling. This stock has never displayed any 

 noticeable crawling symptoms. Yet all the time Nosema has been present in 

 it, sometimes in enormous quantities (see PI. I. fig. 4 — a microphotograph, 

 taken in the present year, of the colon contents of an apparently healthy bee 

 from this stock). 



It is significant that, while G9 contained Nosema over a prolonged period, 

 it failed in any marked way to infect the apiary generally. We have not 

 found Nosema distributed in the bees of all the stocks, but only in a few 

 stocks at any one time, and where it occurred, Isle of Wight disease was not 

 present. 



History of certain Stocks in Lewis — with special reference to the alleged 

 connection between Nosema apis and Isle of Wight Disease. 



We visited Bayble on 7th May 1914, and took samples of a stock of bees 

 which had no history of crawling. Spores of Nosema were found in several 

 of the bees, the infection being very heavy in a number of cases. On 4th 

 September, when again visited and examined, this stock was in a highly 

 prosperous condition ; it filled the brood box of ten combs and crowded also 

 a super of ten shallow frames filled with honey. On 14th August 1915, this 

 stock was still prosperous and had never shown any crawling symptoms. 

 Sample bees from this stock were taken in September, and these were found 

 to be free from spores. Twenty bees were examined : these were lively, 

 vigorous, and flew readily after two days in transit. The chyle-stomachs of 



