Culture

(kul'-chiir). A name loosely and indiscriminately applied to the act, the liquid or solid medium used, and the product of the proce , in culture-experiments upon microorganisms. The culture-media are of various kinds; mineral liquids, bouillons of various kinds, gelatinous fluids, gelose, potato, serum, etc. These media are first sterilized, usually by heat (see Oven, Sterilization), but po ibly also by chemicals, by filtration, by cold, by steam, etc. The infectious matter is then taken upon a sterilized platinum needle-point, pipet, or other instrument, and transferred to the culture-medium. When the latter is of semi-solid consistency, as gelatin, the inoculation by the needle is called Stab-culture, Stichcultur (Ger.), or par piqure (Fr.)., the needle being thrust into the substance. When smeared over the surface, it is called smear culture, Strichcultur (Ger.), or en stries (Fr.). The macroscopic features of the subsequent development give important means of differentiation. For example, when the inoculated matter forms a ma in the medium, pointed below and rising like a nail-head above, it is called en clou, nail-shaped. Then the medium may be liquefied or not, variously colored, peculiarly changed, sediment deposited or not, etc. Subsequent microscopic examination of the culture-product, inoculation-experiments upon animals, etc., complete the study. Culture-bulbs, culture-cells, culture-fluids, culture -media, culture-ovens, culture tubes, etc., are among the equipments of the bacteriologist. C.-oven. See Oven .