38 THE BACTBEIA OF THE APIAKY. 



appeared in the hive when the following method was used : The agar 

 from plates on which the culture was grown was finely crusht and 

 mixt with sterile sirup. A jelly glass, in the lid of which holes had 

 been punctured, was filled and inverted on strips of wood inside the 

 hive. In this way the bees take up the culture with the sirup as 

 rapidly as it flows out of the glasses. A colony having brood free 

 from Bacillus alvei was fed in the above manner on August 8, with 

 repeated feedings on the 9th, 10th, 12th, 13th, 15th, and I7th. On 

 the 12th Bacillus alvei was found in the living larvse and on the 17th 

 many larvae were dead under cappings and some were dead which 

 were not capped; all were soft and of a dull color. Many of the 

 capped cells containing dead larvse had their capping freshly punc- 

 tured. Bacillus alvei was usually obtained from these larvse in pure 

 cultures. In no cell examined where the cell capping was punctured 

 did we find gas-producing organisms; this fact would suggest the 

 conclusion that these punctures which are found in the capping in 

 foul brood are made by the bees and not by gas-producing organ- 

 isms. During this series of inoculations the days were quite cool 

 and sometimes cloudy and damp. On the 20th of August the tem- 

 perature was much higher, the bees were more active, and much of 

 the dead brood had been cleaned out by the bees. On the 22d no 

 dead brood was noticed by casually looking over the brood nest. On 

 the 24th of the same month a careful search was made by uncapping 

 all the cells of one brood frame, and 12 decaying larvaj of a brown 

 color were found. At this time the larvse were not viscid. All the 

 remaining dead brood had evidently been cleaned out by the bees. 

 A condition similar to this, where only a few scattered about in the 

 brood nests contain dead larvse, occurs sometimes in affected apiaries. 

 Two other colonies which were near by but not inoculated gave no 

 signs of disease. 



Mr. N. D. West reports that the climatic conditions seem to have 

 something to do with the extent of the ravages of European foul 

 brood, since the disease is much more destructive in cool, damp 

 weather. This seems to be a very plausible idea. The larvaj at such 

 times may receive more infected food than when fresh is being 

 rapidly gathered; the resistance of the body of the larvse to the 

 growth of Bacillus alvei is at such times much lessened; and the 

 adult bees being less active, the dead larvse are not cleaned out of the 

 combs so rapidly. The results of the experimental work seem to 

 confirm this theory. 



Distribution of Bacillus alvei in Infected Hives. 



In order to combat this disease it is well to know where these patho- 

 genic bacteria may be found. The following is a summary of the 

 results of the investigation along this line : 



