Excepting the greater mastoidal breadth and generally larger size of the skull, the cranial features distinguishing males of _spadix_ from _longicauda_ are features in which _spadix_ shows approach to _noveboracensis_. This is true, in _spadix_, of the relatively longer (in comparison with _longicauda_) rostrum, relatively lesser zygomatic breadth, relatively shallower braincase measured at the anterior end of the basioccipital, and relatively deeper skull as measured at the posterior borders of the last upper molars. This same approach to _noveboracensis_ already has been pointed out with respect to color of the upper parts and is evident also in the relative shortness of the tail which averages only 51 per cent of the length of the head and body rather than 55 per cent as in _longicauda_. Because the _longicauda_ type of animal previously has been regarded as specifically distinct from the _noveboracensis_ type of animal, comment is offered below on selected specimens, referred to _spadix_, which are regarded as intergrades with _noveboracensis_ or with other subspecies. No. 8722, Univ. Wisconsin, adult male, in the white winter coat, from north central Itasca County, Minnesota, obviously has characters of _M. f. spadix_ or _longicauda_ that occur to the west and _M. f. noveboracensis_ of the east. Selected outstanding characters of _longicauda_ are its long tail, anteriorly truncate tympanic bullae and large teeth. Characters indicating its affinities with _noveboracensis_ are smaller size of skull, general narrowness of skull, and relatively low tympanic bullae. The skull is intermediate as regards several individual structural features. For example, although long and narrow and in this feature more nearly approaching _noveboracensis_, the skull is wider than usual in that subspecies and thus approaches that of _longicauda_ or _spadix_. The hind foot, in the dried state, measures 47 millimeters. This large hind foot, obviously long tail (the specimen lacks external measurements), and anteriorly truncate bullae constitute basis for here referring the specimen to _spadix_. However, the seemingly small size of the body and the narrow skull clearly show relationship to _noveboracensis_.