POUL-BBOOD. 475 



the bees, which is never the case with the other disease because 

 of the sticky adherence of the dead matter to the cell wall. 

 Decaying larvae that have died of this disease have no ropiness 

 usually and cannot be stretched out in a string as with the 

 other disease. There is very little odor from the dead larvae 

 and when there is any, it does not resemble that of a "glue 

 pot" which is characteristic of the more dangerous foul-brood. 

 The odor more resembles that of soured brood. 



The methods of treatment of the two diseases differ greatly 

 and will be mentioned farther. For a more complete descrip- 

 tion of bacillus pluton, see "Bacteria of the Apiary," U. S. 

 Bureau of Entomology, Technical Series No. 14, by G. F. 

 White, Ph. D. 



789. Bacillus larvae or foul-brood proper is a more malig- 

 nant disease. It may be very clearly described. 



DESCRIPTION OF MALIGNANT OR AMERICAN FOUL-BROOD. 



"In most cases the larva is attacked when nearly ready to 

 seal up. It turns slightly yellow, or grayish spots appear on it. 

 It then seems to soften, settles down in the bottom of the cell, 

 in a shapeless mass, at first white, yellow, or grayish in color, 

 soon changing to brown. At this stage it becomes glutinous 

 and ropy; then, after a varying length of time, owing to the 

 weather, it dries up into a dark coffee-colored mass. Usually 

 the bees make no attempt to clean out the infected cells, and 

 they will sometimes fill them with honey, covering up this dried 

 foul-brood matter at the bottom. 



"Sometimes the larvae do not die until sealed over. We have 

 been told that such may be easily detected by a sunken cap- 

 ping perforated by a 'pin-hole.' This is by no means invariably 

 the case. Such larvae will often dry up entirely, without 

 the cap being perforated or perceptibly sunken, although it 

 usually becomes darker in color than those covering healthy 

 larvae. 



"The most fatal misapprehension has been in regard to the 

 smell of the disease. In its first stages there is no perceptible 

 smell, and it is not until the disease has made a considerable 

 progress that any unusual smell would be noticed by most per- 

 sons. In the last stages, when sometimes half or more of the 



