8 1 8 Disease of Bees in the Isle of Wight, [feb., 



taken. Smear preparations, made from the contents of the colon of 

 both diseased and healthy bees, showed very large numbers of bacteria. 

 These belonged to several species, but, on morphological grounds alone, 

 none could with certainty be identified as occurring only in diseased 

 specimens. An attempt was therefore made to differentiate the 

 organisms by cultures on several media, and by these means a number 

 of different species were isolated. All the species isolated from diseased 

 bees were, however, discovered in healthy specimens. These 

 investigations were rendered unsatisfactory owing to the number of 

 film-forming organisms, which were almost invariably present, and 

 which rapidly overgrew the cultures. 



In consideration of the fact that certain differences, both anatomical 

 and histological, were found between the chyle stomachs of healthy 

 and diseased bees, my attention was finally concentrated on the contents 

 of these organs. 



It was soon discovered that certain .plague-like bacilli were 

 frequently observed in smears made from the internal lining and 

 contents of the diseased chyle stomach, but were never seen in similar 

 smears from healthy specimens.* Out of 108 smears from diseased bees, 

 67 (62 per cent.) contained these organisms and 34 did not, while 

 in 7 a few doubtful bacilli were noticed. My attempts to cultivate 

 these organisms were not very successful. Primary cultures were 

 always difficult to obtain, but when the organism had become 

 accustomed to artificial media, after two or three generations it grew 

 well. Very frequently no plague-like bacilli grew in the cultures even 

 when the smears had shown them in large numbers. 



In the attempts to get constant results in the primary cultures, a 

 number of different media were tried : agar, glucose agar, saccharose 

 agar, honey agar, and agars containing various sugars, together with 

 bee larva extract (bee agar)t, gelatin, potato, broth, glucose broth, serum 

 broth, honey broth, bee-honey broth, bee peptone water, and others. 

 Cultures were often made in series, one series being cultivated at room 

 temperature, one at 25 0 C. and one at 37 0 C. No differences were 

 observed except in the rate of growth, which was more rapid at the 

 higher temperatures. In none of these media did the plague-like bacilli 

 grow readily in primary cultures, either serobically or anserobically. 



Altogether cultures on various media were made from 60 diseased 

 bees, and in those made from 21 (35 per cent.), plague-like bacilli 

 grew in greater or smaller numbers. From only a small proportion 

 of these, however, was it possible to obtain pure cultures. As controls, 

 cultures were made from 42 healthy bees, but plague-like bacilli were 

 never cultivated. Many cultures from the chyle stomachs of both 

 healthy and diseased bees, even when sown with abundant material, 

 showed no growth.! 



A number of sections of both diseased and healthy chyle stomachs, 



* In only two preparations from healthy bees were a few doubtful organisms 

 seen. 



t Bacillus larvae, probably the cause of American Foul Brood, will only 

 grow on media to which bee larva extract has been added. (White, 1906, 

 P- 43-) 



X When a mass of chyle stomach is placed on the surface of a gelatin slant 

 the medium round it is rapidly liquefied, but frequently no bacterial growth 

 occurs. 



