1. A method of analyzing particles for a plurality of species, comprising the steps of: (a) providing: (i) a plurality of morphology types; (ii) a plurality of spectrum types; (iii) a plurality of target classes, each of said target classes corresponding to one of said morphology types and one of said spectrum types, and (iv) a relationship between a descriptor vector and a concentration vector, said descriptor vector including a plurality of elements, each element of said descriptor vector corresponding to a different one of said target classes, said concentration vector including a plurality of elements, each element of said concentration vector corresponding to a different one of the species; (b) acquiring a plurality of images of the particles, each of said images being acquired at a different wavelength; (c) inferring said descriptor vector from said plurality of images; and (d) using said relationship to infer said concentration vector from said descriptor vector.