Additional records.—Total number, 7 (British Museum), from Brazil, as follows: Pará, Santarem, Santarem ([Thomas], 1912:89; 1920:277), 3; Amazonas, Manaus, Acajutuba ([Thomas], 1920:277), 2; Manacaparú, Manacaparú ([Thomas], 1920:277), 2.
Proechimys semispinosus (Tomes)
Figs. 33, 36. Proechimys semispinosus liminalis, female, MN no. 6253, Rio Quichito. Type. × 1.
Figs. 34, 37. Proechimys semispinosus amphichoricus, male, AMNH no. 77020, Mount Duida. Type. × 1.
Figs. 35, 38. Proechimys semispinosus kermiti, female, AMNH no. 37124, Lower Rio Solimões. Type. × 1.2 (from photograph).
General characters.—Size large; tail short and hairy; aristiforms wide and stiff, especially well-developed on back; general color on upper parts some shade of ochraceous, usually much darker on back and forming a conspicuous dorsal band; feet dark; ventral surfaces and inner sides of legs white; skull elongate and strong with ridges well developed; incisive foramen long and narrow; bullae large; usually four counterfolds in M3 and M2; usually three but sometimes four counterfolds in M1 and even P4; lower premolar with four and lower molars with three counterfolds.