132 THE ROYAL SOCIETY OF CANADA 



in water before cooking any traces of lime left in the fish would be 

 washed away. 



Other Growth Reqiiirements. — We have shown in a preceding 

 series that this organism is a peptone bacterium, and as in the account 

 of the manufacture of solar salt from sea water the red appearance 

 of the evaporating salt water occurs in certain of the reservoirs, an 

 experiment was made in order to find out if the red organism would 

 grow in brine solutions alone, and to see what effect traces of organic 

 substances would have on its development. 16 per cent, solar salt 

 in distilled water was tubed with filter paper strips and sterilized, 

 varying amounts of codfish broth, or agar, were added, with the 

 following results. 



1. 16 per cent, salt — no growth in 21 days. 



2. 16 per cent, salt + 1 drop of fish broth — trace of red growth in 

 one tube. 



3. 16 per cent, salt +2 drops of fish broth — slightly more growth 

 than in 2. 



4. 16 per cent, salt + 3 drops of fish broth — slightly more growth 

 than in 3. 



5. 16 per cent, salt+4 drops of fish broth — still more growth. 



6. 16 per cent, salt + 5 drops of fish broth- — ^abundant growth. 



7. 16 per cent, salt+a small strip of agar — no growth in 21 days. 



Growth definitely increased in direct ratio with the increasing 

 amounts of fish broth, but it is interesting to note that 1 drop of 

 fish broth gave colour. This was a dilution of 1 to 250. 



A number of tubes of 16 per cent, solar salt solution were prepared 

 by adding a small portion of Irish Moss {Chondrus crispus) to each 

 tube. Some of these tubes were sterilized, giving jelly-like con- 

 sistency to the brine. Others were not sterilized. All were inoculated 

 with the red organism, and incubated at 37° C. for thirteen days. 

 In the sterilized tubes growth was moderate but distinct, increasing 

 in amount up to twenty days, while in the unsterilized it was slight. 



As in a previous experiment we have shown that solar salt alone 

 will not support growth, and in another experiment — the examination 

 of brines from some of the reservoirs (salinas) — we have shown that 

 the red organism lives and grows in a concentrated brine, in which 

 at one period at least there was an accumulation of seaweed, there- 

 fore the above experiment with Irish Moss seems to prove that this 

 material, when added to brine, gives sufficient nutriment or organic 

 matter to support the growth of the red organism. 



