Fig 



Movement prior to 

 foulbrood. 



death in European 



not so much likeli- 

 hood that it is car- 

 r.'ed by the bee- 

 keeper on his 

 hands and clothing 

 as is the case with 

 American foul- 

 brood, nor does 

 empty equipment 

 seem to spread the 

 disease as readily 

 as is the case with 

 American foul- 

 brood. 



Diagnostic Char- 

 acters: Any weak 

 colony in the 

 spring may be sus- 

 pected and should 

 be carefully exam- 

 ined for this dis- 

 ease. Its presence 

 or absence cannot 

 be determined by 

 the appearance of 

 the adult bees. The 

 infection of the lar- 

 va probably takes place during the second day of its life, when the in- 

 fected material is given to the larva with its feed by the nurse bees. 

 The action of the disease is very rapid and the larva dies in about two 

 days after the germ has been introduced into its body. Thus most of 

 the larva die before they have completed the fourth day of growth, or 

 before they have left the bottom of the cell, which means that they are 

 still curled. The appearance of a dead larva is very characteristic. Its 

 general color is that of putty; the larva appears to have melted 

 down, and it has lost Its usual shining, glistening and pearly white ap- 

 pearance. After the tissue melts down the tracheal or breathing system 

 of the larva seems to stand out in relief and usually is observed by the 

 beekeepers for the first time. As the larva dries down it develops 

 into a scale, which never has any suggestion of chocolate color as is 

 true in American foulbrood. The scale is loose in the cell so that 

 it can be shaken out by tipping up the comb. The odor of the larva 

 is not particularly characteristic, but is described as "sour". The body 

 contents of the larva are simply "watery" and not "ropy". 



Some toher organisms, but principally Bucillus alvel, may be found at 

 most any time along with European foulbrbood. These are called sec- 

 ondary invaders and are germs which live upon decaying tissue, after 

 the larvae have died from European foulbrood. Their presence may 

 cause an unusually dark color and there may be a tendency to "ropi- 

 ness"- These secondary germs make a condition midway between 

 those typical of European and of American foulbrood. In such cases 

 it is necessary to use extreme care in making the diagnosis. 



Seasonal History: This disease seems to be most prevalent in the 

 later spring, particularly when the weather is exceedingly unfavorable, 

 with cold, damp, raw days prevailing. The disease is not commonly 

 observed after weather conditions become settled in the late spring. 

 Occasionally cases are evident thruout the early summer, but these 



