50 C D AND O THEK SALT FISH FOR THE MARKET. 



Gelatin. Like the development in bouillon, the gelatin may be 

 neutral, faintly acid, or faintly alkaline without perceptibly affecting 

 the development. In a gelatin stab the growth is mostly on the sur- 

 face, a flat, rather thin layer forming, which is about 10 mm in 

 diameter, in from three to four weeks. The color is a bright red 

 with a pale border, shining and viscous. The puncture is tapering, 

 and, except near the surface, without color. No liquefaction takes 

 place and no odor develops. The gelatin is darkened slightly near 

 the surface. 



A gar. On agar there is a more abundant growth than on gelatin, 

 the surface layer is thicker, not so deep in color, and may cover the 

 surface of the medium. In agar plus 1.5 per cent potassium hydroxid 

 the growth was thinner and paler, with a tendency to spread. The 

 puncture is the same as in gelatin. 



Since the red growth is found on fish having salt crystallized on 

 the surface and is also found in the scum on the saturated brine in 

 the butts, it was thought that addition of salt to the agar might aid 

 in development. This was tested, using 5, 10, 15, 20, and 25 per cent, 

 respectively. Development was delayed slightly in the 5 per cent 

 and considerably in the 10 per cent, none taking place in the agar 

 containing the larger amounts. The growth was thinner, but deeper 

 in color, with the addition of the salt. The Trapani salt was first 

 used, then compared with refined salt, the latter checking the growth 

 even more than the former. 



Sea-salt gelatin. Gelatin was made, using sea salt dissolved in 

 1,000 cc distilled water instead of beef broth. This makes a clear 

 gelatin that keeps well. In this the growth was slightly ahead of 

 the control at first, then slightly less, and in a couple of months no 

 difference could be noted. 



Bread paste. This was made by adding sufficient sterilized water 

 to finely ground bread crumbs to moisten thoroughly. It was ster- 

 ilized for fifteen minutes on three consecutive days. The organisms 

 grew well on this medium, forming a bright-red waxy growth on the 

 surface. No color was imparted to the paste adjoining. 



Rice. Rice grains were placed in about three times their volume 

 of water and sterilized in the same way as the bread paste. On this 

 the growth was fair, forming a thin spreading layer. On rice paste 

 made with about six times the volume of water, so that the mass was 

 watery, the organism grew around the swollen grains, and in about a 

 month the whole mass had a pink tint. In paste to which a trace of 

 sodium carbonate was added the growth was better than on the rice 

 alone, being about as thick as on agar. 



Pea broth. To make the broth the liquor was poured off of a can 

 of peas and a can of water added, after which the peas were boiled 

 for about half an hour, filtered, an egg added to clear the solution. 



