XVI. Methods of Identification and Study

In order to identify an organism after isolation, tube, plate, and other cultivations must be prepared, incubated under suitable conditions as to temperature and environment, and examined from time to time (a) macroscopically, (b) by microscopical methods, (c) by chemical methods, (d) by physical methods, (e) by inoculation methods, and the results of these examinations duly recorded.

It must be stated definitely that no micro-organism can be identified by any one character or property, whether microscopical, biological or chemical, but that on the contrary its entire life history must be carefully studied and then its identity established from a consideration of the sum total of these observations.

In order to give to the recorded results their maximum value it is essential that they should be exact and systematic, therefore some such scheme as the following should be adhered to; and especially is this necessary in describing an organism not previously isolated and studied.