200 
Diseases of Fish 
pericardium, the cavity was seen to be filled with a dense mass of fibrin 
and a slightly cloudy liquid. The heart was much hypertrophied, but 
no endocarditis or valvular disease was present. The walls of the heart, 
with the exception of the region of the apex of the ventricle, were 
tightly bound down to the walls of the pericardium by the fibrin 
formation. The hypertrophy of the heart and partial organisation of 
the fibrin showed that the condition was of long standing. 
Before the pericardium was opened, the wall was seared with a red 
hot seeker, a platinum needle introduced, and cultures made on sloped 
peptonised fish gelatine. 
In the course of a few days a number of cream coloured colonies 
developed: these did not liquefy the gelatine. Subcultures in broth, in 
the course of 48 hours at the room temperature, became cloudy and 
formed a yellowish sediment at the bottom of the tube. 
These growths consisted of pure cultures of a slender diplobacillus 
with rounded ends. The bacilli were about 1'75/a in length and 
arranged end to end: they stained with the ordinary basic dyes but not 
by Gram’s stain. Sections of the fibrinous mass in the pericardium 
showed fibrin, which was partially organised in the region nearest 
the pericardial wall, leucocytes, and the diplobacilli described above. 
A Recurrence of the ‘Salmon Disease ’ in the Colne. 
In May of this year several specimens of chubb and roach which 
had died infected with a white fungus growth were sent to me for 
investigation. 
It was reported that large numbers of trout, chubb, roach, and eels 
were dying in the Hertfordshire Colne from the same cause. 
Before death the fish swam slowly near the surface of the'water and 
seemed very weak, their sense of equilibrium appeared to be diminished 
or lost, and the gill covers moved rapidly as though the fish were being 
asphyxiated. Small patches of white fungus usually appeared first on 
the head, adipose fin, and bases of the other fins: these then spread 
along the sides and coalesced until finally nearly the whole fish was 
covered with the growth. The epidermis and scales were more or less 
completely destroyed in the affected areas. 
The specimens were sent packed in ice. 
Examination of the fungus showed that it resembled Saprolegnia 
ferax\ cultures from it were made in flasks containing boiled sterile 
