of the Fishery Board for Scotland. 



39 



of the fish, when the ulceration was not so advanced, and where there was no 

 loss of continuity of tissue, small greyish-white spots were seen, where the 

 scales were falling off, and rubbed off very readily, while the tissues beneath 

 were very red and congested. 



Bacteriological Examination. 



Four of the fish, two haddocks and two whitings, were removed in sea- 

 water tanks to Marischal College. While the fish were still alive scrapings 

 were made from the ulcers by means of sterilised platinum wire and plated 

 out on gelatine, Agar and fish-agar media, and incubated at 20 °C. and 

 37 °C. respectively. 



Smears were also made on glass slides .from the ulcerated areas. 



The fish were then opened by abdominal section under sterile conditions. 

 Then cultures and smears were made from both the peritoneal fluid and 

 heart blood by sterilised platinum wire, Streak cultures were also made of 

 the peritoneal fluid on Digralski and Conradi media. 



Microscopical Examination op the Smears. 



Smears from the Ulcerated Areas. 



These were stained with the ordinary basic aniline dyes — M ethylene 

 Blue, Dilute Carbol Fuchsin, Gram's Stain, etc. All these preparations 

 showed the presence of cocci which were strongly Gram positive ; also 

 some rod-shaped and many vibrio-like micro-organisms, which in hanging 

 drop preparations were actively motile. 



Blood Smears, 



These were treated precisely as the last, and in two of the fish examined 

 the blood showed the presence of cocci, which were strongly Gram positive. 



Smears from the Peritoneal Fluid. 



These, when treated as the above and examined, did not show the presence 

 of any micro-organisms. 



Examination of Cultures. 

 .Cultures from Ulcerated Areas. 



The gelatine plates were examined 48 hours after inoculation. Many small 

 colonies of a brownish-yellow tint were seen in the media, and around these 

 liquefaction of the media was just seen to be commencing. Also a smaller 

 number of bluish-white colonies around which there was no liquefaction of 

 media. The Agar plates were also examined 48 hours after inoculation. 

 Numerous colonies of a dirty whitish colour with a yellowish to orange 

 tint were seen. There were also present a few large superficial colonies, and 

 a few deep colonies of a brownish-white colour. 



From these different colonies, sub-cultures were made on the following 

 media : — 



Gelatine tubes — Streak and shake cultures. 



Agar tubes — Streak cultures. 



Litmus peptone milk. 



Bouillon. 



Potatoes, 



and incubated at 20°C. and 37°C. respectively. 



