On Inflammation in Fishes. 



231 



collect, from time to time, sufficient of a yellow fluid which 

 presented all the microscopic characters of pus, but was 

 generally mixed more or less with muscular fibre, however 

 gently I pressed it along the seton track. I had made the 

 wound in the largest fish too transverse, and the water 

 flowed through it, so that I obtained no satisfactory results 

 until I made the water so shallow that this portion of his 

 back was left bare, or floated him up with corks ; I could 

 then obtain some good yellow pus. 



Not only did the irritation of the setons induce the forma- 

 tion of matter, but they produced a destructive ulceration 

 in the smaller fish ; the substance was lost subcutaneously, 

 until merely a layer of skin covered the threads, and the 

 orifices of the wound grew daily wider. In the larger fish 

 the tissue over the seton became of a purplish colour, and 

 at the end of three weeks the latter had nearly cut its way 

 out. After removing them the wounds speedily healed. 



Eeing now anxious to see how wounds were repaired in 

 these animals, I cut a piece off the larger fish's back, taking 

 care not to injure important parts, as the spine. This ap- 

 peared very cruel, but so far as ordinary evidences of sensa- 

 tion go, it seemed to him a matter of total indifference ; he 

 would make no movement if you scratched or pressed the 

 surface of the wound ; and so far from its affecting his ap- 

 petite, he ate in one night twelve sticklebacks, six minnows, 

 and four tadpoles, in addition to vegetables. 



For a fortnight this wound remained unaltered in appear- 

 ance, except that it appeared sodden by the water ; then 

 three large straight blood-vessels were seen distinctly cross- 

 ing it in an antero-posterior direction ; and in twenty-four 

 hours they were again obscured by a thick film, which grew 

 thicker and denser, and then separated, floating off upon the 

 water, and leaving a bright pink surface exposed ; this 

 changed to a darker hue, and granulations sprang up. I 

 never saw any pus on the surface even when it was kept out 

 of the water, the granulations did not bleed readily, but the 

 raw surface now seemed very sensitive to pain ; the unfor- 

 tunate fish seemed to dread the slightest touch ; letting fall 

 a drop of water over his part of the bath set him splashing 



