Formerly mammals were given full specific rank but later as a result of further knowledge of range the number of species decreased while the number of subspecies increased. Examples are given in Peromyscus. weasels and coyotes. Thinking now is in terms of trinomials rather than binomials as was the case 50 years ago. However, most variability throughout the range of a species could be shown on a map by symbols instead of by subspecific names. Neofiber alleni is given as an example and a new map showing the range and morphological variation by means of symbols is compared with older maps in which subspecific names are used.