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much longer life than the worker bee and to live a different kind of 

 life. It may be that the queen does contract the disease, although 

 she does not die before or along with her worker offspring. In this 

 connection one feature has impressed us in reviewing our results 

 from experiments with queens. We are not satisfied that the 

 production of queens from Isle of Wight diseased stocks is as good 

 as that of queens of similar age from healthy stocks. This problem 

 is the subject of investigation at present. 



Qeneral Conclusions. — In the course of our enquiries we have 

 had ample opportunities of studying this disease in all its aspects. 

 The following statements are based entirely upon our own observa- 

 tions and experiments, some of which are not given in detail in the 

 foregoing paper. 



The presence of this disease in a stock is manifested by the 

 inability of the worker bee to fly. In fine weather during the 

 working season stricken bees leave the hive and loiter upon the 

 alighting board, or crawl upon the ground or grass in front. They 

 frequently climb the stems of grasses or other plants. They tend, 

 especially as the day advances and the weather becomes cooler, to 

 gather in clusters upon the ground, where they remain almost 

 motionless, except for occasional trembling of the wings and body, 

 until they die. When the weather is not too cold they may survive 

 a night's exposure, and if warmed become more active. But 

 individual bees, once they are stricken with the disease, do not 

 recover, and this independently of whether they have suffered from 

 exposure outside the hive or not. Notwithstanding the fatal 

 nature of the disease, we have been able to keep alive for two 

 months in the autumn a remnant of an affected stock in which 

 practically every bee was unable to fly and showing all the ordinary 

 indications of the disease. Within the hive, as we have noted in 

 sick stock kept in observation hives, the smitten bees do little 

 work, they feed little, and frequently show so great weakness that 

 they fall from the frames. Not uncommonly they immediately 

 attempt to regain their position by climbing back again. They 

 may show their weakness further in lack of co-ordination of the 

 fore and hind wing, the latter frequently projecting at right angles 

 to the body. Very usually the hind gut (colon or rectum) is 

 dilated with undischarged faeces. We regard this as largely due to 

 the incapacity of the bee for flight, defecation normally taking 

 place only on the wing. The faeces are usually at least semi-solid 

 in character, but when the temperature of the hive is high and there 

 is liquid food (syrup or honeyj the condition may become 

 dysenteric. 



These familiar symptoms indicate the final phase of the disease, 

 and we have proved its presence in bees while still capable of 

 flight. Our results suggest that infection takes place most readily 

 through contact with sick bees, and that this may occur in the early 

 phase of the adult condition, before the bee has commenced to 

 forage. It is not certain that drones contract the disease, although 

 they may suffer indirectly through the disorganisation of the hive 

 economy when the disease is widespread within it. We have 

 already indicated our results regarding the relation of the disease 



