130 A NEW BACILLUS PATHOGENIC TO FISH. 



non-sporulating organism, Bac. salmonicida,* which is pathogenic 

 to salmon. Wyssf found Bac. vulgare to be the cause of a disease in 

 freshwater fish. Sieber| describes an organism under the name of 

 Bac. piscicidus agilis, which was responsible for the death of fish 

 in an aquarium. This organism differs from Bac. inscicidus 

 bipolaris in its production of gas in gelatine and agar culture, its 

 growth on potato, and its pathogenicity to certain rodents. 



EXPLANATION OF PLATES. 



Plate viii. 



Fig. 1. — Section through stomach wall of original fish (Bream), stained 

 with methylene-blue ( x 500) . 



Fig. 2. — Bacilli from a 48 hours' at 20° C. agar culture, stained with methy- 

 lene-blue ( x 1000). 



Plate ix. 

 Fig. 3. — Young surface colony on gelatine plate ( x 50). 



Fig. 4. — Various forms of the surface and sub-surface colonies in agar 

 plate culture, 48 hours at 20° ( x T 7 5 ). 



* Lehmann and Neumann, Diagnostik, ii.. 240. 

 t Wyss, Centralblatt fiir Bakt. 1 Abt. xxiv., 936. 

 t Sieber, Centralblatt fiir Bakt. 1 Abt., xvii., 888 



