24 MISCELLANEOUS PAPERS ON APICULTURE. 



that their introduction is not recent. This evidence is not merely the 

 result of bee keepers' reports or of more or less semiauthoritative and 

 indefinite rumors, but it is based upon results of bacteriological find- 

 ings in numerous samples of brood comb sent to this Bureau by the 

 bee keepers in the State during the past year and a half. Under 

 these conditions bee keeping can not be brought to the high degree of 

 perfection which is possible. No factor in bee keeping tends to limit 

 the industry as do epidemics of such diseases ; they cause bee keepers 

 to become discouraged by " bad luck " and to lose interest in their 

 bees. The " luck " must change ; the bee keepers must learn the 

 nature of the diseases, where they exist, and how to combat them; 

 otherwise the industry will decrease even more. 



THE TWO KNOWN BEE DISEASES. 



Two contagious brood diseases of bees are now known. These 

 attack the developing brood and so reduce it that the colony soon 

 dwindles from lack of young bees to replace the old. They are 

 known, respectively, as American foul brood and European foul 

 brood. 



AMERICAN FOUL BROOD. 



The cause of this disease is definitely known to be an organism, 

 Bacillus larva' White. It is what has been heretofore frequently 

 designated simply as " foul brood." The nature of the disease is 

 described by Dr. E. F. Phillips, in charge of apicultural investiga- 

 tions in this Bureau, as follows : 



When the larvae are first affected they turn to a light chocolate color, and 

 in the advanced stages of decay become darker, resembling roasted coffee in 

 color. Usually the larvae are attacked at about the time of capping, and most 

 of the cells containing infected larvae are capped. As decay proceeds these 

 cappings become sunken and perforated, and, as the healthy brood emerges, the 

 comb shows the scattered cells containing larvae which have died of disease, still 

 capped. The most noticeable characteristic of this infection is the fact that 

 when a small stick is inserted in a larva which has died of the disease, and 

 slowly removed, the broken-down tissues adhere to it and will often stretch 

 out for several inches before breaking. When the larva dries it forms a 

 tightly adhering scale [of characteristic and diagnostic shape and] of very 

 dark brown color, which can best be observed when the comb is held so that a 

 bright light strikes the lower side wall [of the cell]. Decaying larva 1 which 

 have died of this disease have a very characteristic odor which resembles a poor 

 quality of glue. This disease seldom attacks drone or queen larvae. 



EUROPEAN FOUL BROOD. 



This is the disease which appears to be most prevalent in Massa- 

 chusetts, probably having swept in from New York State, where it 



"The brood diseases of bees. By E. F. Phillips, Ph. I). Circular 79, Bureau 

 of Entomology, U. S. Department of Agriculture, pp. 1-2, 1906. 



