BACILLI. 129 



Bacillus lepr^. Microscopically. — Almost identical with the 

 tubercle bacillus, but is found in different relations to the cell elements 

 of its host. 



Bacillus malaria (Klebs). — A small organism found free in the 

 Pontine Marshes and in the swamps of America, 2 to 7 /x. in length 

 by 1 p. in breadth, growing into long fibrils, and multiplying by 

 transverse cleavage. By some it is supposed to be the cause of 

 malaria. 



Bacillus of Blue Milk. In Milk. — A dark purple colour is 

 produced by the rapid multiplication of the organism. The milk 

 does not curdle, and retains its ordinary consistence. 



In Gelatine. — A small rounded mass occupies the surface of the 

 jelly at the seat of inoculation, and from this a delicate opaque 

 spike passes downwards in the track of the inoculating wire, and the 

 whole of the jelly becomes tinged with a peculiar green tint, which 

 is modified according as it is viewed with direct or oblique illumina- 

 tion. 



Microscopically. — Short rods 2*5 /x. long which are often connected 

 end to end. In fluid media they perform rapid movements similar 

 to those of B. tenno. 



Fluorescing bacillus. — See description of Fig. 36, p. 81. 



Violet bacillus. — See description of Fig. 35, p. Si. 



Bacillus of Mouse Septicaemia. — In gelatine, it grows rapidly, 

 giving the appearance of a very attenuated cloud, most distinctly 

 visible by oblique illumination. The appearance is due to the 

 bacilli, each lengthening into a spiral fibril in the jelly mass. 



Microscopically. — They are extremely small rods, only 1 /x. in 

 length and o-i //.. in breadth, so that they are only to be seen with 

 very high powers of the microscope. They occupy the liquor 

 sanguinis and the interior of the white blood corpuscles of the 

 blood of the house-mouse, but they are unable to develop themselves 

 in that of the field-mouse. ■ 



MICROCOCCI. 



Micrococcus prodigiosus. On Potato, Bread, &-r. — Forms a thick 

 creamy film of an intensely bright crimson colour, which grows with 

 great rapidity, and covers the whole of the nutrient surface (Fig. 19, 

 p. 6!). 



In Gelatine. — It causes liquefaction rapidly, and gives its character- 

 istic hue to the liquid portions. 



/// Milk, &*c. — It produces a deposit with the typical crimson 

 colour. 



1 



