Fig. 125. Distribution of the porcupine, Erethizon epixanthum in Washington. Boundaries between ranges of subspecies are uncertain.
In Washington the single young is born late in May or early in June. There are two pairs of mammae, both pectoral, of which only the anterior are functional.
Erethizon dorsatum epixanthum Brandt
Erethizon epixanthus Brandt, Mem. Acad. Imp. Sci. St. Pétersbourg, ser. 6, 3 (Sci. Nat. vol. 1): 390, 1835.
Erethizon dorsatus epixanthus True, Proc. U. S. Nat. Mus., 7:600, 1885.
Erethizon epixanthum epixanthum [Miller], U. S. Nat. Mus. Bull., 128:437, April 29, 1924.
Erethizon dorsatum epixanthum [Anderson] and [Rand], Canadian Jour. Research, 21:293, September 24, 1943.