. Diseases of bees. Bees. Apr. 12, 1924 Development of American Foulbrood 135. that of larvse at the age when European foulbrood makes its attack, comprises nearly 45 per cent of the dried substance, or nearly 14 per cent of the fresh substance. From these facts it may be assumed that, because of the great amount of food given the larva at this age, there must be present in the larval intestine, at all times during the active feeding period, considerable amounts of this food rich in sugar unassimilated, up to and even after active feeding ceases. A number of larval and prepupal intestines were
. Diseases of bees. Bees. Apr. 12, 1924 Development of American Foulbrood 135. that of larvse at the age when European foulbrood makes its attack, comprises nearly 45 per cent of the dried substance, or nearly 14 per cent of the fresh substance. From these facts it may be assumed that, because of the great amount of food given the larva at this age, there must be present in the larval intestine, at all times during the active feeding period, considerable amounts of this food rich in sugar unassimilated, up to and even after active feeding ceases. A number of larval and prepupal intestines were dissected from healthy larvse and tested roughly with Benedict's qualitative solution {34) for the presence of reducing sugars. The results indicated the presence of relatively large amounts of reducing sugar in the intestines of larvse just prior to sealing. Little or no reducing sugar could be demonstrated in the intestines of sealed larvse or prepupoe. It may therefore be assumed that certain of the organisms associated with the early stages of European foulbrood are able to grow in the presence of a high sugar concentration. Experiments were devised in which a medium containing 10 per cent dextrose was used. It was found that while a few types of organ- isms, such as one resembling Streptococcus apis {S8), could be grown in varying numbers, an organism sim- ilar to that described by Maassen (S9), resembling the larger'forms of Bacillus pluton, called Bacillus lanceolatus, could be isolated and grown from over 50 per cent of the samples cultured. As described by the writer (.4'^), "This organism was found to grow best on a 10 per cent dextrose yeast extract agar with a reac- tion slightly acid. It is differentiated from Bacillus pluton and Streptococcus apis in being gram-negative, and does not grow readily if at all in media with- out ; From these studies it was suggested that possibly this comparatively high sugar content of the unassimilated food in the l
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