Externally _goldmani_ resembles _Neotoma lepida_ (examples from California, Utah, and Colorado) in having long, silky pelage; ochraceous buffy coloring, especially along sides; and underparts basally plumbeous except for a small throat patch where the hairs are entirely white in some individuals. In _albigula_ this patch of white hairs usually is much larger and more conspicuous. Cranially, instead of resembling the _lepida_ group (including _Neotoma stephensi_), _goldmani_ looks more nearly like a miniature _albigula_ (specimens of _albigula_ from Coahuila). The auditory bullae, in relation to the length of the skull, are of comparable size in _goldmani_ and _albigula_ whereas those of the _lepida_ group are proportionately much larger. Moreover, the posterior margin of the palatal bridge is concave in _goldmani_ and _albigula_ instead of truncate as in the _lepida_ group. _Neotoma goldmani_ differs from both _albigula_ and _lepida_ in: ascending branches of premaxillaries broader posteriorly; supraorbital ridges less pronounced; rostrum less massive; interparietal broader in relation to width of cranium; interorbital space, relative to length of skull, wider; and upper molar teeth broader in relation to their length. [Illustration: FIGURE 1. Distribution of the pigmy woodrat, _Neotoma goldmani_. Solid circles represent specimens examined; hollow circles represent others reported but not examined.] The baculum of _goldmani_, when compared with bacula and with figures of these bones in Burt and Barkalow (Jour. Mamm., 23:291 and 293, August 13, 1942) of species representing the _floridana_, _lepida_, _albigula_, _mexicana_, _fuscipes_, and _cinerea_ groups, was found to resemble most closely the baculum of _albigula_ in general proportions (ratio of length to lateral diameter of base) and in having a distinct knob at the distal end. The baculum of _goldmani_ differs slightly from that of _albigula_ in having a less downwardly curved shaft and in having a less pronounced median dorsal depression at the proximal end. Although _goldmani_ bears some external resemblance to _lepida_, the cranial characters mentioned above and the size and shape of the baculum show that _goldmani_ is best arranged as a member of the _albigula_ group. [Illustration: FIGURE 2. Dorsal, end (proximal), and lateral views of the baculum of _Neotoma goldmani_, adult, No. 40758 KU, x 5.] Measurements (in millimeters) of the mature baculum (fig. 2, No. 40758 KU) are: total length, 6.2; lateral diameter of base, 2.6; dorso-ventral diameter of base, 1.4; lateral diameter of the shaft near the middle of the bone, 0.6. Except for being smaller, the bacula of the younger _goldmani_ are like the mature ones.