Bacterium Zopfii, Kurth. 



Origin. — Isolated from the intestines of chicken; also 

 from water and feces. 



Form. — Rods, two to five times as long- as wide. It 

 forms threads, which in gelatin are often peculiarly bent 

 or twisted, resembling spirals. In old cultures coccus-like 

 involution forms are abundant. 



Motility. — ^It is actively motile. 



Sporulation. — Spore-like bodies are formed, which 

 are said to resist desiccation, but are readily destroyed by 

 heat, and are readily stained by anilin dyes. These in 

 reality are not spores, but involution forms. 



Anilin dyes. — It is stained easily. 



Growth. — Rapid. 



Gelatin plates. — The colonies' form delicate cloudy patches of 

 radiating threads, and show, under the microscope, in addition to the 

 network of threads, numerous rounded little masses or bunches of 

 cells. 



Stab cultv/re. — Marked growth in the upper part of the tube, but 

 absent from the lower part. It shows fine radiating lines vhich, at 

 or near the surface, penetrate deepest into the surrounding gelatin. 



Btreak cultwre. — On agar, it forms a very thin, dry, grayish growth. 



Oxygen requirements. — It is an obligative aerobe. 



Temperature. — It grows best at ordinary temperature. 

 It can grow at 37-40°, but tends to develop involution 

 forms and to die out. 



Behavior to gelatin. — No liquefaction. No indol. 



Pathogenesis. — No effect has been observed on animals. 



This organism resembles in some respects certain 

 species of the Proteus group and, indeed, is considered by 

 some to be identical with the P. Zenkeri. 



1 When surface colonies, as those above, present some special 

 characteristic they can be reprinted on cover-glasses. To make 

 such -an impression or "Klatsch" preparation, select a suitable 

 spreading colony, with the aid of a No. 3 objective, then raise the tube 

 of the microscope and carefully drop a clean cover-glass on top of 

 the colony. Apply gentle pressure with a pair of forceps, then grasp 

 the edge of the cover-glass and carefully remove; allow to dry in the 

 air; fix and stain in the usual manner. 



In making the reprint only the growth should adhere to the 

 cover-glass. Considerable gelatin, solid or liquid, on the cover-glass, 

 is undesirable and interferes. 



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