THE CAUSE OF EUROPEAN FOUL, BROOD. 9 



If the disease is more advanced than either stage represented in 

 figure 8 when this test is applied, a portion of the intestinal content 

 may flow out in the form of a sac, the wall of which is very easily 

 broken. When broken the content of this saclike structure will flow 

 out as a rather thin whitish or yellowish-white fluid containing small 

 whitish granules that vary in size. If the disease is far advanced 

 and the larva probably dead, the enveloping substance of the intes- 

 tinal content is so easily broken that often only whitish or yellowish- 

 white fluid with its granular content flows from the ruptured Avail of 

 the larva. 



Figures 2 and 6 represent healthy larvae, and at these ages the seg- 

 ments of the body are strongly marked off. Living larva? at these 

 ages, if suffering from European foul brood, frequently show these 

 markings less distinctly as represented in figures 3, 4, and 7. This 

 sign, too, may asssist in the selec- 

 tion of larvse that are suspected 

 of being diseased. 



THE VALUE OF EARLY SYMPTOMS IN THE 

 DIAGNOSIS OF EUROPEAN FOUL BROOD. 



These symptoms of European 

 foul brood are some of the more 

 important ones that are observed 

 in sick larvse or in those only 

 recently dead. They are espe- 

 cially valuable in the study of 

 the disease in the experimental fig. Q.—Bficuuts piuton in a stained smear 



colony. Thev have not been used preparation from sick lary^P at stage rep- 



• . resented in a, figure 8. (Original. > 



by the apiarist for making a 



diagnosis. The symptoms of European foul brood that have been 

 looked for by the bee keeper for the most part are the evidences of 

 disease which obtain as a result of the death of the brood. The 

 post-mortem symptoms as manifested by the dead larva? themselves 

 have been the most positive evidences used by the bee keeper in 

 diagnosing the disease. It is hoped, however, that when they are 

 well learned, the symptoms of European foul brood observed in 

 living larvse and in those very recently dead may prove of value in 

 the apiary as well as in the experimental colony. 



Practically all the later symptoms of European foul brood have 

 also been observed during the course of the disease in the experi- 

 mental colony. This fact is used as evidence that the disease which 

 was produced in the experimental colony was the same as that encoun- 

 tered in the apiar3\ Since the diseased material for making the 

 inoculations has been received from various sources and the disease 

 produced was apparently the same in every case, the conclusion that 



