28 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



Agar slant. — A faint band with leafy margins is formed by the second day. It spreads to the 

 tube at the bottom and becomes somewhat thicker, but is always a very thin, translucent layer 

 without color. The deposit in the water at the bottom is white. 



Gelatin stab. — Growth occurs quite deep down, and a whitish layer forms on the surface, 

 which is only about 1 mm. in diameter, and has irregular margins. By the third day from the 

 upper part of the stab delicate offshoots pierce tlie gelatin, which soon reach nearly 

 to the tube wall and resemble the leaves of asparagus. The growth on the surface 

 extends in a barely perceptible layer until, after two weeks, the surface is largely 

 covered. There seems to be some softening at the surface after eighteen or twenty 

 days, but no liquefaction can be made out. 



Potato. — A thin layer of moisture, very faintly yellowish, is seen on the second 

 day. It becomes thicker, and about the color of honey on the third or fourth day, 

 and is moist, smooth, and shiny. After a week it becomes a chocolate brown, but 

 does not increase in thickness. 

 Gci. stab. Bouillon. — Becomes diffusely cloudy on the third day. After a week the growth 



begins to settle to the bottom, and the liquid is left tolerably clear. 

 Eosolic acid. — Becomes slightly darker after ten days. 



Li /mas milk. — Becomes more blue after a week. At the end of two weeks it is a sky-blue. 

 There is no coagulation of the casein, but a white precipitate collects at the bottom of the tube. 

 After live weeks the color is somewhat lighter, but a pure blue. Reaction is amphoteric. 



Sugar gelatin, deep stab. — Growth quite deep down and on the surface. There is more lique- 

 faction than in plain gelatin. No gas is formed. 

 Indol. — Negative reaction. 



Relation to temperature. — More rapid and abundant at 35° to 36° C. 



Note. — This bacillus does not form glutinous masses on any culture medium, but seems to 

 have the power of holding other growths to it. The bacillus Geminus minor was found with it, 

 and it was with much difficulty that the two were separated. A portion of the growth was placed 

 in Dunham's solution, and repeatedly shaken at intervals for two or three hours, and from this 

 plates were made. It was only after repeated trials that the two were gotten out in pure culture. 



Bacillus Geminus Minor. 



Found at a depth of 4 feet in made soil, which had been paved for several years, in close union 

 with the bacillus Geminus major. 



Character. — Requires oxygen for its development. 



Morphology. — Very short straight rods, with rounded ends, from two to four times as loug as 

 broad. Occurs singly. 



Spore formation not observed. 



Motility. — Very active movements, like fighting or playing. 



Flagella not demonstrated. 



Colonies on gelatin plates. — Colonies become visible in twenty-four to thirty hours. At the 

 end of thirty-six hours the deep are whitish punctiforni dots, while those on the surface are white 

 also and one-sixth of a millimeter in diameter, x SO. Deep are yellowish in color, coarsely' gran- 

 ular, with even margins. The surface colonies are much the same, only showing a nucleus. 

 By the third day the surface colonies have become pearly white, are evenly circular, and have 

 rounded surfaces. They are so dense that little can be seen under the microscope. Near the 

 edges they have a wavy appearance, as if made up of serpentine parallel lines closely packed. 

 After ten days they have become 1.5 mm. iu diameter, are more elevated, and are a pearly white. 

 They retain their circular outline and have well-defined edges. They become too dense to show 

 any structure under the microscope. The deep colonies remain unchanged, except to increase 

 iu density. There is no liquefaction of the gelatin. 



Agar slant. — A thin greenish-white line is formed by the second day. It spreads rather 

 slowly, grows more white, and in eight or ten days has covered much of the surface of the agar 

 in a thin shiny-looking layer, which runs to the bottom. 



