Part 18

Pelage.--Aristiforms on middorsal region: Gray basally, gradually blackening toward tip; total length, 21 to 27 mm; maximum width, 0.6 mm. Aristiforms on outer thighs: Gray basally, gradually blackening toward middle, and Ochraceous-Buff on distal half; total length, 18 to 21 mm; maximum width, 0.5 mm. Setiforms on middorsal region: Gray basally, gradually blackening toward tip but interrupted by short, Ochraceous-Buff, subapical zone; total length, 18 to 20 mm; maximum width, 0.06 mm. Setiforms on outer thighs: Gray basally, gradually blackening toward middle, and distal part Ochraceous-Buff or with only tip blackened; total length, 14 to 16 mm; maximum width, 0.05 mm.

Skull.--Slender; bullae small but well-inflated; upper edge of jugals deeply concave; transverse ridge of jugals conspicuous; postorbital process of zygoma small, involving only squamosal; incisive foramen elongate (5 x 2.5 mm); vomerine sheath almost always incomplete, and maxillary part lacking or, when present, slender; mesopterygoid fossa extending forward as far as middle of second molars; posterior palatine foramina at plane of front border of first molars or slightly anterior thereto.

Teeth.--Upper molariform teeth with two counterfolds in 10 of 16 specimens and only one in remainder; these folds commonly coalesced; M3 with only one counterfold in 6 specimens, and 2 counterfolds in remainder. Lower molariform teeth with two counterfolds in 6 specimens and in 10 of them m3 has only one counterfold.

Comparisons.--From P. i. panema, gratiosus differs in: Lower molariform teeth with only one counterfold in smaller percentage of specimens; incisive foramen shorter; aristiforms narrower; setiforms Ochraceous-Buff instead of Cinnamon. Differences from iheringi and paratus are given in the accounts of those subspecies.

Remarks.--All the animals were captured in climax forest.

Specimens examined.--Total number, 16 (MN), from Brazil, Espirito Santo, Santa Teresa, Floresta da Caixa Dagua, altitude 750 meters.

=Proechimys iheringi panema= subspecies nova

Type locality.--Campinho, Colatina, Espirito Santo, Brazil; altitude 500 meters. Type: Museu Nacional, no. 8288, adult female; collected on 15 July, 1942, by C. Lako.

Range.--Known only from the type locality.

Diagnosis.--Aristiforms moderately wide; tail of approximately same length as head and body; setiforms Cinnamon; incisive foramen moderately long and narrow; vomerine sheath incomplete; upper molariform teeth with two counterfolds, but m3 most frequently with one.

Pelage.--Aristiforms on middorsal region: Gray basally, gradually blackening toward tip; total length, 21 to 23 mm; maximum width, 0.8 mm. Aristiforms on outer thighs: Gray, some gradually blackening toward tip and others with distal part Cinnamon; total length, 17 to 19 mm; maximum width, 0.7 mm. Setiforms on middorsal region: Gray, gradually blackening toward tip, but interrupted by Cinnamon, subapical zone; total length, 18 to 20 mm; maximum width, 0.06 mm. Setiforms on outer thighs: Gray, gradually blackening toward middle, and Cinnamon on all of distal parts or with tip blackish; total length, 13 to 15 mm; maximum width, 0.09 mm.

Skull.--Strong, with jugals dorso-ventrally wide; interorbital region and cranium wide; bullae well inflated; transverse ridge of jugals not well-developed; postorbital process of zygoma small and formed only of squamosal; incisive foramen 4.7 × 2.2 mm; vomerine sheath always incomplete, with maxillary part reduced to small process; mesopterygoid fossa extending forward as far as middle of second molars or only slightly short thereof; posterior palatine foramina at plane of front of first molars.

Teeth.--All upper molariform teeth with two counterfolds in 4 specimens; one having only one counterfold in M3; 3 with counterfolds coalesced in one or two molars. Lower molariform teeth with two counterfolds in one specimen, these counterfolds not coalesced; m3 with one counterfold in 4 specimens and with two in one specimen.

Comparisons.--Differences from P. denigratus and P. i. paratus are given in the accounts of those animals.

Specimens examined.--Total number, 5 (MN), from Brazil, Espirito Santo, Colatina, Campinho; altitude 500 meters.

=Proechimys iheringi denigratus= subspecies nova

Type locality.--Mata do Ribeirão da Fortuna, 40 kilometers west of Ilheus, Itabuna, Bahia, Brazil. Type: Museu Nacional, no. 8500, adult male; collected 16 March, 1945.

Range.--Known only from the type locality.

Diagnosis.--Aristiforms wide and stiff; tail longer than head and body; setiforms near (15''a) Cinnamon; incisive foramen long and narrow; vomerine sheath complete; premolars with two counterfolds, upper molars with one or two, and lower molars with only one.

Pelage.--Aristiforms on middorsal region: Gray basally, gradually blackening toward tip; total length, 20 to 22 mm; maximum width, 1.1 mm. Aristiforms on outer thighs: Gray basally, gradually blackening toward tip or with distal part near (15''a) Cinnamon; total length, 14 to 16 mm; maximum width, 0.5 mm. Setiforms on middorsal region: Gray basally, gradually blackening toward tip but interrupted by near (15''a) Cinnamon, subapical zone 4 mm wide; total length, 18 to 20 mm; maximum width, 0.05 mm. Setiforms on outer thighs: Gray basally, gradually blackening toward tip but interrupted by wide, near (15''a) Cinnamon, subapical zone.

Skull.--Slender; nasals short; bullae large and well-inflated; jugals with conspicuous transverse ridge; postorbital process of zygoma conspicuous, spiniform and formed almost exclusively by jugal; incisive foramen elongated and narrow (5 × 1.8 mm); vomerine sheath complete and formed almost exclusively by premaxillae; maxillary part of this sheath short and in most specimens the two parts of sheath completed by vomer itself; mesopterygoid fossa extending forward as far as middle of second molars and in some skulls as far as anterior border of second molars; posterior palatine foramina at anterior plane of first molars.

Teeth.--Upper molariform teeth: P4 always with two counterfolds; M1 with two counterfolds in 65 per cent of specimens but anterior counterfold poorly developed; rest of specimens with only one counterfold in M1; M2 with two counterfolds in 50 per cent of specimens and only one in remainder; M3 with two counterfolds in only 17 per cent of specimens, and remainder with only one. Lower molariform teeth: p4 always with two counterfolds; molars always with only one counterfold.

Comparisons.--From P. i. panema, denigratus differs in: Each lower molar with only one, instead of with more than one, counterfold; incisive foramen longer and narrower; vomerine sheath complete instead of incomplete; aristiforms conspicuously wider; tail longer.

Remarks.--One female (SEPFA no. M 17060) captured on 9 January, 1944, gave birth to two females on 26 January, 1944. Each of these young measured 177 mm in total length and weighed 27.8 g. On 4 March, 1944, their measurements were: head and body, 120,120; tail, 120,130; hind foot, 32,33; ear, 21,22; skull:--total length, 36.0,35.0; condyloincisive length, 29.0,29.1; zygomatic breadth, 19.1,18.5; length of nasals, 12.5,11.6; interorbital constriction, 9.3,8.8; cranial breadth, 16.4,16.9; palatilar length, 11.5,10.5; crown length of P4 and M1, 4.3,4.3 mm.

The forest where the animals were captured has a high percentage of deciduous trees in spite of the heavy rainfall in this region. All of the animals were trapped near water. Young were captured from January to May. Most animals have a conspicuous Cinnamon patch on the nuchal region.

Specimens examined.--Total number, 34 (SEPFA 33, MN 1), from Brazil, Bahia, Itabuna, Mata do Ribeirão da Fortuna.

=Proechimys iheringi paratus= subspecies nova

Type locality.--Floresta da Capela de São Braz, Santa Teresa, Espirito Santo, Brazil; altitude 630 meters. Type: Museu Nacional, no. 4012, adult female; collected on 24 September, 1940, by Dr. H. W. Laemmert; SEPFA no. M 8447.