626 Bulletin American Museum of Natural History. [Vol. XXXIV, 
indicated, but the type specimen, an immature animal, was obtained by the 
Spix Expedition (according to Wagner, /. c., 1844, p. 48), which spent much 
time exploring that part of the Amazonian region, which includes the lower 
Rio Madeira and lower Rio Negro. Wagner (I. c.) states that Spix’s type 
came from the same region (Gegenden) as Natterer’s specimens. Dasy- 
procta nigricans Wagner was based on specimens collected by Natterer in 
part at Villa de Borba, on the lower Rio Madeira, with which Wagner (J. c., 
1844, p. 48) compared Wagler’s type and considered it identical with 
Natterer’s specimens, but he did not adopt Wagler’s earlier name. The 
~ type locality of fuliginosa may therefore properly be designated as Villa de 
Borba, on the basis of the known type locality of nzgricans. Five specimens - 
collected by Leo E. Miller (Roosevelt Brazilian Expedition) at Calama, a 
short distance above Borba, on the lower Rio Madeira, are here regarded 
as typically representative of negricans and hence also of fuliginosa. 
The collector’s measurements of an old adult male and an old adult 
female are as follows: Total length, & 630, 2 590; tail, 30, 20; hind foot 
Crtisio) 125, 9 A380: Skulls of the same specimens: Total length, & 109.5, 
2 114; condylobasal length, 7 101.5, 2 104; zygomatic breadth, 7 53.5, 
2 47.5; imterorbital breadth, 7 33, 9 32; diastema, 7 29.4, 9 28: maxil- 
ay toothrow, co 29.4, 2 29.7. 
_ This series shows some individual variation in coloration, but the aver- 
age condition may be indicated as follows: Upperparts black, the tips of 
the hairs narrowly annulated with pale yellowish or white, with a broad band 
of black along the middle of the dorsal region; hairs of the lower back and 
rump greatly lengthened, intense black, with long white tips, forming a con- 
spicuous veiling of the surface; ventral surface grizzled whitish and dusky, 
the midline whitish, the annulations of the hair-tips often tinged with pale 
yellowish. 
Lhe Dasyprocta fuliginosa group is evidently closely related to the D. 
varregata group, and it will probably be found that the two constitute a single 
large assemblage of local forms, ranging over the greater part of South 
America. Dasyprocta aurea Cope! from Chapada, Matto Grosso, is the 
southeastern representative of the group, D. colombiana of the Santa Marta 
district and D. csthmica of Panama are the northern forms, D. variegata and 
D. yungarum of Peru and Bolivia the southwestern forms, with the two 
described below, from Ecuador and western Colombia, completing the west- 
ern periphery of the area of distribution. D. colombiana seems to represent 
the maximum in size and to form the connecting link between the dark 
fuliginosa forms of the central Amazonian Basin and the lighter or more 
oh For further reference to this species see below, p. 633. 
