48 COD AND OTHER SALT FISH FOR THE MARKET. 



needle point. The viscosity does not seem to be so great in the pin! 

 spots when first appearing as on the older and redder spots, but i 

 can be demonstrated by placing the infected point in a small drop o: 

 water on a slide and working the needle round in the drop, thei 

 drawing it gently away, when elastic threads are formed that are a: 

 long as those from the older infection. The viscosity makes it diffi 

 cult to separate the organisms, and often, in spite of the most vigor 

 ous preliminary shaking, the resulting colonies will sometimes sho^ 

 mixtures, and as the development of all three organisms is very slov 

 the detection of the mixtures is correspondingly slow. Then agaii 

 very few colonies develop on a plate, so that after some preliminary 

 trials no dilution was used in making plate cultures directly from th< 



fish. 



coccus. 



The coccus is the organism which produced the reddening both 01 

 artificial media and on fish. This form occurs in pairs and tetrads 

 and less frequently, singly. The coccus varies in size, the averag< 

 being about 2 to 2.5 /* in diameter; sometimes larger cocci occur, vary 

 ing from 3 to 5 /A in diameter. When these were first seen, since the^ 

 correspond in size with the coccus described by Dantec, it was sup 

 posed that there was a mixture, but as many times a pair will b< 

 found composed of a large and a small coccus, or a tetrad with one 

 two, or three large ones joined respectively to three, two, or one smal 

 ones, the occurrence seemed to be merely an idiosyncrasy of develop 

 ment. At first, when the large cocci were noted in the red growth 01 

 fish or in an artificial culture, isolation cultures were made, but th 

 resulting development in no case gave a colony composed of the larg 

 cocci. In a vigorous growth the four cells of a tetrad, the member 

 having different sizes, can be seen in process of formation, sometime 

 a divisional line showing in the large cell. No spores have been ob 

 served. In artificial media the coccus is nonmotile, but occasional!; 

 from a culture on fish some may show a tumbling movement, but thi 

 is slow and deliberate. So far flagella have not been noted, thoug 

 cultures of various ages and on various media have been tested 

 Lowit's method being used. The organism is capsulated, the capsul 

 being seen readily in both unstained and stained preparations. Whei 

 grown on solid media a viscous mass is formed which draws out hit 

 elastic threads and which adheres to the needle ; in liquid media, som 

 days after the liquid becomes turbid, zoogloea masses of various size 

 form on the surface. 



The color varies from a pink to a bright red, the red having 

 stronger and more oily appearance than the pink. Usually the pin! 

 appears in the young cultures, but occasionally both the gelatin an< 

 .fish will have the bright-red color from the start. When examine 



