EXPERIMENT STATION BULLETINS 211 



BACTERIA— WHAT THEY AEE, WHAT THEY DO, AND HOW 



THEY ARE CULTIVATED. 



BY C. E. MARSHALL. 



Bulletin No. 139. — Veterinary Department. 



GLOSSARY. 



Aerobes. — Bacteria which require free oxygen. 



Agar-Agar. — A preparation of dried sea weed found on the eastern coast of A.sia. 

 Anaerobes. — Bacteria which will not live where there are traces of free oxygen. 

 Arthrospores. — Bacterial cells which assume the characteristics of spores. 

 Asporogenic. — Applied to bacteria incapable of producing spores. 

 Bacillus (plural, bacilli).— A rod-shaped micro-organism. 



Bacteria (singular, bacterium). — A generic name representing the entire class of micro- 

 organisms. 

 Bacterium. — In the generic sense the singular of bacteria; in specific sense, a very short 



, rod or bacillus. 

 Biological. — Pertaining to the study of life. 

 Blood-corpuscles. — Circular cells existing in blood. 

 Blood serum. — The straw colored liquid expressed from blood clot. 

 Bouillon. — A beef tea containing dry peptones. 

 Brownian motion. — A vibratory motion. 

 Capsules. — A gelatinous substance enveloping bacteria. 



Carbon. — A chemical element entering into the composition of all organic compounds. 

 Cell. — The ultimate division of organized living matter. 

 Cellulose. — A woody fiber- like substance. 

 Cell-wall,— h. sheath enveloping a cell. 



Chain. — Several micrococci joined together as a string of beads. 

 Chromogenie. — Applied to bacteria producing pigment. 

 Cilia (singular, cilium). — Lash-like appendages. 

 Clostridium.— T>eB\gnates an enlargement at the middle of a bacillus, produced by the 



formation of a spore. 

 Colony. — An aggregation of bacteria springing from a single micro-organism. 

 Culture. — Bacteria under cultivation in a suitable soil. 

 Diplococcus (plural, diplococci). — A kind of micrococci arranged in pairs. 

 Disinfection.-^ A process by which pathogenic bacteria are rendered inactive, or killed. 

 .Endospores.— Spores formed within a cell. 



Fermentation.— A. process of chemical change instituted by a ferment as produced by 

 J easts or bacteria. 



