Maech 7, 1902.] 



SCIENCE. 



375 



meters. The plug fits snugly inside of the 

 cylinder, but may be turned from right to 

 left easily by a lever attached to a post 

 on top of the plug. This post passes 

 through a hole in the cap. A delivery tube 

 is screwed on to the bottom of the cylinder, 

 and is attached at a point 90° from the 

 opening in the top cap to the funnel. Di- 

 rectly over the delivery tube a little hole 

 is drilled through the cap to serve as an 

 air vent. 



When one of the chambers in the plug 

 has been filled with the medium, the lever 

 is reversed and, as the chamber passes over 

 the delivery tube, the medium is discharged 

 into a test-tube below. 



An Unusual Bacterial Grouping: Maby 

 Hefperan, University of Chicago, Chi- 

 cago, 111. 



An organism presenting peculiar mor- 

 phological characteristics, obtained from 

 Krai's Laboratory Collection, Prague, was 

 sent under the name of B. rosaceus metal- 

 loides. This organism produces an orange- 

 red pigment, but differs from the original 

 description of the above-named form in 

 three important cultural features, viz., 

 lack of metallic luster, for which B. rosa- 

 ceus metalloides is peculiarly known, non- 

 liquefaction of gelatin to any active degree, 

 and possession of the power of mo- 

 tion. A hanging drop preparation from a 

 bouillon culture of seventy-two hours, room 

 temperature, shows the characteristic 

 grouping to best advantage. Short small 

 bacilli, about the size of B. acidi lactici, are 

 seen grouped together in aster-like clusters 

 varying in composition from but three or 

 four bacilli up to fairly compact spherical 

 burrs of rodlets radiating from a center. 

 The number of these asters increases in a 

 culture for several days, especially at the 

 surface, where they are loosely packed to 

 'form a reddish surface scum. There 

 seems to be nothing like a capsule or a gelat- 



inous zoogloea massing. Below the surface 

 a greater number of free motile bacilli are 

 present. In old cultures the asters are ir- 

 regular and fewer in number, free bacilli 

 predominating. On solid media the aster 

 formation has been observed only on agar 

 cultures. The bacilli are longer and more 

 slender than in bouillon, and, when stained, 

 show the Volvox-like grouping very beau- 

 tifully. On potato the bacilli are short and 

 thick, and may show well-defined capsi;les 

 enclosing two rods. 



Observations on the important question 

 as to whether the asters are formed by cell 

 division as a process of growth, or by a 

 method akin to agglutination, are as yet 

 incomplete. The regularity of the forma- 

 tion, the occurrence on solid as well as in 

 liquid media, and the final disappearance' 

 of the asters, point, however, to the conclu- 

 sion that this phenomenon is a growth 

 phase in the life-history of the organ- 

 ism. 



An Improved Method of making Collodion 

 Sacks: C. S. G-orsline, M.D., LTniversity 

 of Michigan, Ann Arbor, Mich. 

 Apparatus. — A long test-tube or other 

 tube, closed at one end except for a 

 perforation 2-Al mm. in diameter, and hav- 

 ing a caliber corresponding to the diam- 

 eter of the desired sack ; a wide-mouthed 

 6-8 oz. bottle one-third full of colorless 

 collodion of U. S. P. strength, and a few 

 ounces of distilled water. 



Manipulation. — Touch the perforated 

 end of the tube to the surface of the col- 

 lodion, thereby obtaining a film of col- 

 lodion over the opening, but none inside. 

 Allow this to dry a few moments. Incline 

 the bottle containing the collodion as much 

 as possible without spilling, and insert the 

 tube, rotating slowly, allowing only the 

 lower one-fourth to be immersed in the 

 collodion. Withdraw from time to time to 

 allow partial drying to take place, repeat-' 



