. British bee journal & bee-keepers adviser. Bees. 84 THE BRITISH BEE JOURNAL. [Feb. 27, 1896. enable us to understand somewhat of the nature of this disease. Bacillus alvei is a pathogenic or disease- producing micro-organism, in form cylindrical or rod-shaped, and increasing by splitting or fissuration. The rods increase in length with- out growing thicker, and at a certain point divide and separate in two, to again increase, divide, and separate. Sometimes, in suitable nourishing media, the lengthening of the rod is not accompanied by separation, but only by repeated division into longe
. British bee journal & bee-keepers adviser. Bees. 84 THE BRITISH BEE JOURNAL. [Feb. 27, 1896. enable us to understand somewhat of the nature of this disease. Bacillus alvei is a pathogenic or disease- producing micro-organism, in form cylindrical or rod-shaped, and increasing by splitting or fissuration. The rods increase in length with- out growing thicker, and at a certain point divide and separate in two, to again increase, divide, and separate. Sometimes, in suitable nourishing media, the lengthening of the rod is not accompanied by separation, but only by repeated division into longer or shorter chains of bacillus-filaments, or leptothrix. The rods are also provided with a flagellum at one end, suffers no damage at that temperature. Freezing also kills the bacilli, but not the spores. In the same way chemical reagents, completely destructive of the bacilli, do not affect the vitality of the spores. Carbolic acid, phenol, thymol, salicylic acid, naphthol beta, per- chloride of mercury, and many other substances, even when considerably diluted, prevent the growth of bacilli, but have no effect whatever upon the spores. The great resistance of spores to high and low temperatures, to acids and other substances, is due to their being encased within a thick double membrane. There are certain chemical substances which. Fig. 1.—Foul Brood in an advanced stage. and are endowed with the power of locomotion. Under certain conditions bacilli have the power of forming spores, in which case a speck appears at a particular point of the bacillus, which gradually enlarges and develops into an oval, highly refractive body, thicker but shorter than the original rod. The spore grows at the expense of the protoplasm of the cell, which in time disappears, setting free the spore. The latter formation closes the cycle of the life history of the bacillus. The spores—repre- senting the seeds—retaiu the power of germi- nating into bacilli when introduced into a suitable nouris
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