On this basis of designating age, the holotype of _C. pediculus_ is young and nearer the juvenal than the subadult stage. Its small size is partly the result of its youth. Other than its small size we find no characters to distinguish it from _C. m. mearnsi_. Unfortunately no young male of _C. m. mearnsi_ of the same age as the holotype of _C. pediculus_ is available. Also, from the general area of the Sierra Guadalupe, Coahuila, only the one specimen of _Conepatus mesoleucus_ (the holotype of _C. m. pediculus_) is known. Consequently, we can not yet prove that some young males of _C. m. mearnsi_ are as small as the holotype of _C. pediculus_. Because of this lack of proof we tentatively recognize the subspecies _Conepatus mesoleucus pediculus_ instead of placing the name _Conepatus pediculus_ in the synonomy of _Conepatus mesoleucus mearnsi_. The holotype of _C. sonoriensis_ is a young female, older than the holotype of _C. pediculus_, and approximately midway between the juvenal and subadult stages. The holotype of _C. filipensis_ is an adult male. We suppose that _C. mesoleucus mesoleucus_ Lichtenstein and _C. mesoleucus mearnsi_ Merriam on the one hand, and _Conepatus leuconotus leuconotus_ Lichtenstein and _C. l. texensis_ Merriam on the other hand will be found to intergrade, in which event the name _Conepatus leuconotus_, having page priority over _Conepatus mesoleucus_, will apply to the species. Proof of complete intergradation is not yet available. The one difference between the two that prevents our uniting them as subspecies of one species is the larger size of _C. l. leuconotus_ and _C. l. texensis_. Measurements of the smallest adult male and female available to us of _C. l. texensis_ and of the largest adult male and female of _C. m. mearnsi_ are given below.