_Teeth._--P4 with four counterfolds in one of five specimens and with three in remainder; M1 with four counterfolds in three of five specimens and with three in remainder; M2 with three counterfolds in one specimen and with four in all four remaining specimens; M3 always with four counterfolds. Lower premolars with four counterfolds and lower molars with only three.
_Comparisons._--The subspecies is easily distinguishable from _P. s. angularis_ by: larger number of black setiforms on back, forming an almost black longitudinal band; more elongate skull; larger and longer bulla; longer incisive foramen which is more constricted posteriorly.
_Specimens examined._--Total number, 6 (AMNH), as follows: Venezuela, territ. _Amazonas_, Esmeralda, Mt. Duida, altitude 325 m., 4; Venezuela, territ. _Amazonas_, Rio Cassiquiare, Quemapuré, 1; Brazil, Amazonas, _São Gabriel_, Rio Uaupés or Caiari, Tatú, 1.
_Proechimys kermiti_ Allen, 30 December 1915, Bull. Amer. Mus. Nat. Hist., 34(22):629 (orig. descr.); Allen, 1916, Bull. Amer. Mus. Nat. Hist., 35(30):569; Tate, 1935, Bull. Amer. Mus. Nat. Hist., 68(5):400; Ellerman, 1940, The families and genera of living rodents, Brit. Mus. (Nat. Hist.), 1:119.
_Type locality._--Lower Rio Solimões (up the Solimões 50 to 60 miles on the north bank of the river), _Manacaparú_, Amazonas, Brazil. _Type_: American Museum of Natural History, no. 37124, adult female; collected 20 April, 1914, by Leo E. Miller (Roosevelt Brazilian Expedition).
_Diagnosis._--Upper parts Tawny, with darker longitudinal band on back, gradually becoming Ochraceous-Buff on sides; zygomata widely spread; nasals long; incisive foramen long; vomerine sheath incomplete; only M3 with four counterfolds.
_Pelage._--_Aristiforms on middorsal region_: Grayish basally, gradually blackening toward tip; total length, 18 to 20 mm; maximum width, 0.8 mm. _Setiforms on middorsal region_: Grayish basally, gradually blackening toward tip but interrupted by Tawny, subapical zone 2 mm long; total length, 18 to 20 mm; maximum width, 0.06 mm; some blackened toward tip without subapical zone. _Setiforms on outer thighs_: Whitish basally, gradually blackening toward tip but interrupted by Ochraceous-Buff, subapical zone 2.5 mm long; total length, 18 to 20 mm; maximum width, 0.05 mm.