s 



CIRCULAR 3 9 2, U. S. DEPARTMENT OF AGRICULTURE 



2, B). Dead brood in cells with discolored, sunken, or punctured 

 cappings (fig. 3, B, O, D) should always be studied carefully to 

 determined whether death was caused by American f oulbrood. 



In advanced stages of the disease many of the cappings are 

 punctured (fig. 2, B). Cappings may also be broken away at the 

 edge and settled down on the dead brood, appearing dark brown 

 and shining. Cappings over dead brood are often removed by adult 

 bees, and in advanced cases many dried scales, as the remains of 

 dead larvae and pupae are then called, can be seen in uncapped 

 cells (fig. 3, E and F). 



Figdee 6. — Symptoms of American foulbrood in pupae : A, healthy pupa ; B-F, stages in 

 the decay and drying of pupae, ventral views. 



SYMPTOMS SHOWN BY THE DEAD BROOD 

 KIND AND AGE OF AFFECTED BROOD 



Usually only worker brood is affected, but occasionally drone and 

 queen brood are also killed. Adult bees are never affected by this 

 disease. 



