145 



hive situated two miles distant. As already described, both 

 parent stocks had a recent history of contamination with 

 Nosema apis. 



On 2nd July it was ascertained that there were three frames of 

 fully sealed brood and bees covering six frames, but the queen was 

 missing. A frame of brood with one sealed queen cell was intro- 

 duced from No. ii, a colony with a disease-free history. On the 

 I2th a queen was seen upon the frames, and on the 19th she had 

 begun to lay. At this date fifteen bees were taken and examined 

 for Nosema. No parasites were found. 



On 2nd August two bees were examined and scattered spores 

 of Nosema found in one. No developmental stages were seen. 



In the beginning of September there were five frames of brood, 

 mostly sealed. The bees were covering eight frames and there 

 was a good supply of stores. When examined in December they 

 were found clustered on 4J frames. 



It is to be noted that this stock, which originated in two others 

 known immediately prior to its institution to harbour Nosema apis, 

 has so far not developed recognisable infection with this parasite. 

 This is in keeping with the concurrent history of the parent stocks, 

 in which the parasite could not be found during the same period. 

 In this experiment an opportunity was afforded the parasite for 

 development in bees of Dutch race and in ordinary British bees 

 from two separate sources. 



No. 5. Nosema infected Bees with Queen having Isle-of Wight 

 Disease History.— On 3rd July 1918 a nucleus (No. 13) consisting 

 of about three frames of Italian bees from a stock known to be 

 heavilx- infected with Nosema apis was given a 191 7 queen, trans- 

 ferred from a stock definitely affected with Isle-of- Wight disease. 

 The nucleus during the succeeding two months maintained itself 

 only fairly. The strength attained at the beginning of August was 

 about six frames of bees ; during August this did not increase. It 

 was kept under close observation until the beginning of September, 

 during which period there were no signs of disease nor of any 

 undue mortality in the neighbourhood of the hive. The queen was 

 young, and her production was not equal to reasonable expectation. 

 It is to be remembered that she survived from an Isle-of- Wight 

 diseased stock. 



Nosema apis was looked for on a number of occasions, and was 

 found only upon one of these. So scarce did the parasite appear 

 to be that it would not be safe to attribute the weakness of the 

 stock to this cause alone. 



Summary. — Although the original bees forming this nucleus 

 were abstracted from a stock harbouring Nosema, this parasite was 

 never found in significant numbers of the bees. There were two 

 kinds of bees present, viz. : — Italian and Blacks, during the period 

 of observation, and neither appeared to be materially affected. 

 Infection never spread beyond the casual stage during the three 

 months of the experiment (to ist October). 



The stock was alive in January 1919. A large sample of bees 

 was examined at this date and Nosema was not found. 



