ON ISLE OF WIGHT DISEASE IN HIVE BEES — ETIOLOGY. 



183 



Table II. 



The following illustrates the progress of infection as observed in the periodic 

 examination of 4 stocks of the same apiary : — 



The data set forth in the foregoing Tables are thoroughly representative of our 

 results as a whole. Examination of the figures quoted will show : — 



1. That in every case of a " Sick " stock, Tarsonemus was present in the stock, 



and in a high proportion of cases it was found in every bee exartiined. 



2. That in the majority of stocks marked " Healthy," Tarsonemus was not 



found. 



3. That in a proportion (36 per cent.) of supposed " healthy " stocks, 7'ar- 



sonemus was found. Of these within the period of observation (five 

 months at most) a proportion eventually developed the usual symptoms, 

 and died out from the disease. A proportion died out without having 

 shown the symptom of " mass crawling," and a few remain apparently 

 healthy. 



Regarding the admittedly diseased stocks in which Tarsonemus has been found, 

 we deem further illustration unnecessary. Concerning those other cases, some of 

 which may appear to present difficulties, we consider it important that details should 

 be submitted, and of these we now quote typical examples. 



For ease of comparison the main facts regarding each are summarised at the end 

 of the series. 



TRANS. ROY. SOC. EDIN., VOL. LII, PART IV (NO. 29). 



116 



