26 



cillium stoloniferum). Honey somewhat diluted n water was 

 given them in sterile food cups. No moulds present. June 29. No 

 sign of uneasiness could be seen. July 1. One drowned in the 

 honey. July 3. The remaining still alive. 



Series II. 



July 12. 12 bees were used. 10 c.c. honey were given them. No 

 moulds present. July lh. As lively as when put in the cage. When 

 the cage was knocked the usual roaring sound was heard. July 16. 

 Found clustered together in the morning in one corner of the box. 

 No sign of disease. July 17. All alive but one. 



Series III. 



July 17. 11 bees were used. 10 c.c. honey were given them. No 

 moulds present. July 19. All alive. July 21. Great satisfaction 

 among the bees demonstrated by the rapid vibration of the wings 

 and the elevated abdomens. July 23. All alive but two. 



SeriesIV. 



July 23. 16 bees were used. 10 c.c. honey were given. No moulds 

 present. July 30. All of the bees alive and healthy. 



3. The nature of the toxic substances in the moulds. 



The virulent toxic action of the moulds on bees is clearly de- 

 monstrated in the above. The symptoms of poisoning are on the 

 whole the same irrespective of the mould employed in the feeding 

 experiments. At lirst a feverish haste and rushing is noticeable 

 among the bees. They run around as intoxicated, but only for a 

 few hours. Then there is a stage of great drowsiness accompanied 

 (as in the case of Cladosporium herbarum) by violent trembling of 

 the wings and of the body. At the same time a more or less 

 pronounced swelling of the abdomen is seen. The mouthparts and 

 abdomen are incessantly rubbed and scratched, but after some time 

 the insect becomes inactive and too weak to move about except 

 with great difficulty. It crawls around dragging along the swollen 

 abdomen. Sometimes it makes a few feeble attempts to fly, but it 

 soon lies on its side stretching its legs in the air and dies quietly. 

 The digestive apparatus is found to have undergone same charac- 

 teristic disturbances. Ventriculus and in a still higher degree rectum 



