143 



amount of interference, and further was infected with the parasite 

 Nosema apis. 



With regard to Nosema, it is to be noted that in the first year 

 the infection was noticeably heavy, yet during the breeding season 

 the strength of the stocl< was not affected sufficiently to prevent 

 natural swarming or wintering in normal numbers. While certain 

 of the bees undoubtedly died under heavy infection with the 

 parasite others were found in full working activity, also heavily 

 infected. In the second year, although the parasite survived in the 

 stock over winter, it was never found in very large numbers ; 

 eventually its presence could not be demonstrated afier the middle 

 of June, and we are forced to conclude that if the Nosema infection 

 has not effectually died out it has fallen to a low, and for the time 

 being at least, non-significant, level. As already indicated no signs 

 of disease, e.g. dysentery, crawling, etc., have been associated with 

 the stock during the course of the experiment, and it is doubtful 

 whether the presence of Nosema has proved an adverse feature of 

 much practical importance in this instance. In June 1919 the 

 stock was of full strength and appeared to be prospering well. 



No. 2. History of a Stock Naturally Infected. — A small stock 

 of bees (No. 32) covering less than four frames was obtained in the 

 end of March and placed in a new situation alongside a stock (No 31) 

 harbouring Nosema apis. Sample bees were taken and searched 

 for Nosema at the date of deposition and the result was negative. 



A month afterwards eleven bees were captured on the frames 

 of this stock and examined individually ; one bee was found to 

 have Nosema apis in the spore stage. Three days later twelve 

 more bees were taken, five of which were found to be infected with 

 Nosema apis. 



At the end of May the stock was covering ten frames and had 

 a large amount of brood. Nosema was still present, and spores 

 could be found in the dead bees in the front of the hive. Of five 

 living bees taken, one was found to be infected. Unfortunately at 

 this date the queen appears to have been injured. She was found 

 dead outside the hive. On examination she was proved free from 

 Nosema infection. Queen cells were formed, but no queen was 

 seen on frames up till end of June. On Sth July a frame with 

 brood and queen cells was introduced from No. 3 1 (Dutch bees). 

 A queen was hatched and was seen laying on 22nd July. 



At the end of June a few bees were taken for examination and 

 Nosema was not found. 



On 6th July five bees were taken and these were also found to 

 be free from Nosema. Meantime the stock swarmed. 



During July and August the parent colony, which it may be 

 noted was now headed by a queen bred in the adjacent Nosema 

 infected stock, increased satisfactorily, and in the beginning of 

 August covered nearly ten frames with abundance of stores. 

 Examinations for Nosema were made in August — two bees were 

 tested separately and yielded a negative result, ten were pulped 

 and six smears examined, again the result was negative. 



On I Sth September the strength of the stock consisted of about 

 six frames of bees with brood upon one and a half ; there were 



