146 American Fisheries Societv 



ducted by Dr. W. W. Browne under the Division of Scientific 

 Inquiry of the Bureau of Fisheries on the causes of redden- 

 ing and significant results have been obtained. The cause, in 

 general, has been known for many years to be bacteria; but 

 otherwise little has been known of their origin, or of their 

 peculiarities. 



Briefly stated, the results of the work cited are as follows : 

 The bacteria that cause reddening are of two distinct kinds, a 

 spirochsete which in colonies is pale pink, and a bacillus whose 

 colonies are deep red. The two organisms grow in such close 

 harmony that mixed colonies occur which vary in color from 

 pale pink to deep crimson as the proportions of the two organ- 

 isms present vary. The evidence points to the solar sea salts 

 from the tropical and subtropical seas as the source of the 

 infection. Solar sea salts, both American and foreign, are 

 infected. Mined salts seem to be free from the infection. 



Every species of bacteria is acclimated to some particular 

 set of conditions, some of them almost incredible for living 

 things. These red bacteria are accustomed to live and grow 

 either on moist salt or very strong salt solutions. If bacteria 

 are particularly resistant to some condition, as to strong salt 

 in this case, it does not follow that they are likewise resistant 

 to all severe conditions; it is the bacteriologist's business, by 

 studying all the habits and peculiarities of the organism, to 

 discover its weakest point where attack will destroy it. The 

 strongest resistance of these bacteria, that against salt, is also 

 the weakest, for it has been found that water less than 15 per 

 cent saturated destroys them. Thus, the best and simplest 

 remedy for the trouble is clean, fresh water, and plenty of it. 

 Of course, it would be futile to try to stop the reddening 

 of cod as long as every shipment of salt brings new infection, 

 and the butts, floors, buildings and the surroundings at pack- 

 ing plants are heavily infected. The remedy is to clean up 

 the places completely with cold water and live steam, and to 

 abandon imported solar salts. Facts already given indicate 



