8 DErARTMEXT OF AGRICULTURE 



colonies affected in an apiary where this disease is present, 

 although this cannot be considered the rule. The symptoms of 

 this disease are so variable that often close observation is neces- 

 sary to determine which disease is present in the colony. This 

 disease often works with great rapidity, entirely ruining- the 

 colony in one season. 



Sacbrood 



Another recognized disease affecting bee larvae is known as 

 sacbrood, formerly sometimes called "pickled brood." This 

 disease, according to White', is caused by "a filterable virus.' 

 It causes death in the larva; in an advanced stage of their develop- 

 ment, usually at or immediately after the time of sealing. Often 

 a slight discoloration is noticed in the cappings covering larvse 

 which have died of this disease. Perforated cappings are seen 

 but seldom. Apparently the bees entirely remove the capping* 

 at one operation. 



The dead larvae are found on the lower cell wall, the head 

 outward, usually pointed and slightly turned upward away from 

 the lower cell wall. 



The color is brownish gray to a dirty grayish brown. The 

 head is darker than the body, often being nearly black in color. 

 When dried the dead larva forms a scale which is removable 

 without the least difficulty. 



Practically no odor accompanies this disease, although if a 

 punctured larva is held close to the face a slight yeasty odor is 

 noticed. The larval skin does not decay as readily as the body 

 contents, but remains unbroken, and by careful manipulations 

 the larva can be removed from the cell entire. The body con- 

 tents are watery. The dead larvae show no ropiness whatever. 

 This disease does not usually cause a high mortality, and it is 

 extremely rare to find a colony of bees in New Jersey so badly 

 affected as to cause appreciable loss. 



■White, G. F., 191S. Sacbrood, a disease of bees. U S Dent Ao-r 

 Bur. Ent. Cir. 169. ^ ^ 



