84 HISTORICAL NOTES ON BEE DISEASES. ' 



^laassen says, was obviously due to an acid wliich was present. He 

 likened the condition to that obtained in cultures in those artificial 

 media in wliich a sugar is present. Maassen suggests that the death 

 of Streptococcus apis under these conditions is not without signifi- 

 cance if this organism is the cause of the disease. 



The feeding of pure cultures of Streptococcus apis to healthy colo- 

 nies gave negative results. He reports that negative results were 

 obtained also when healthy colonies were fed larvae containing the 

 cocci with no Bacillus alvei present. When similar larvae, however, 

 were fed to healthy bees together with a suspension of the spores of 

 Bacillus alvei he reports that the disease was produced. 



Having considered the etiology of the "mild" form of foul brood 

 (European foul brood) , Maassen took up for consideration the cause 

 of the so-called "virulent" form of the disease (American foul brood). 

 This latter disease, he says, is far more widespread in Germany than 

 is the former. From 347 samples of diseased brood examined in five 

 years, 294, almost 90 per cent, were affected with the "virulent" 

 form of the disease. In this form he usually found Bacillus hranden- 

 hurgiensis. This species was so named by him because liis first 

 experience with it was m a sample from the Province of Branden- 

 burg, Prussia. Maassen describes the morphology and cultural char- 

 acters of Bacillus hrandenburgiensis. He says that this species is 

 the cause of the foul brood most commonly found in Germany. 



Maassen also says that he found spirochsete-like forms (p. 73) in 

 the unstained decaying "foul-brood" mass. He considers them a 

 good diagnostic agent in the virulent form of the disease. He says 

 further that in the progress of his investigations he found Spiroclixte 

 apis to be nothing more than tufts of the flagella of Bacillus hranden- 

 hurgiensis (p. 82). He also says that after great difficulty two 

 media were found on which Bacillus hrandenburgiensis grew well. 

 One was agar made from bee larvae (p. 62), and the other was 

 agar made from the brains of calf or of pig. Maassen reports that 

 he has produced disease by feeding cultures of Bacillus hranden- 

 hurgiensis. Each colony fed received the cultures from 10 to 20 

 tubes. When considerable culture was fed the disease appeared in 

 from 6 to 10 days after the feeding of the colony. He states that the 

 disease is present in America, and that a bacillus has been found in 

 it which has been named Bacillus larvse. 



Maassen has therefore confirmed most of the facts stated in the 

 paper (p. 80) which was received by him at least four months before 

 his was published. 



The following is a brief summary of Maassen's paper: 

 1. He mentions that he has encountered in his studies two forms 

 of foul brood. These were described by Dzierzon and others. 



