1. A bacteria measuring apparatus comprising: a sampling device for processing a sample comprising fluorescently stained bacteria; a first detector for detecting size information from each of the bacteria in the sample; a second detector for detecting fluorescence information expressing an intensity of fluorescent light emitted from each of the bacteria in the sample; a processor; a memory including programs that enable the processor to execute operations comprising: creating a scattergram of the bacteria using the size information and the fluorescence information as parameters; obtaining a maximum variance direction of distribution of the bacteria in the scattergram by analyzing the distribution in the scattergram; and determining whether the bacteria in the sample are bacillus or coccus based on the maximum variance direction of the distribution.