■4 



()18 



MONO(JI{Al'll8 OF NOUTII AMERICAN ROOEXTIA. 



G. rtintdnoj.H, wliidi is very difrcrciit in siz(! niid color). Colorntion aiul gcncrnl 

 appcaninco of (1. hurmriun (wiiitli lias two distinfit grooves on (Ik; iipjuT 

 incisors). Fur so(t, slcok (ms in other species of the genus, excepting G. his- 

 pldiis, in which it is extremely coarse and harsh). Averaging much larger 

 than any United States species (nearly equaling G. hixpidiis), with propor- 

 tionally smaller pouches and hands, and weaker claws (these jmrts being as 

 in (J. hi,s])iiiu.s). Tail and feet clothed (as usual in the genus), not naked as 

 in G. hisjiitliM ivn\ (J. tuzd. Length, 10-11 inches; tail, about 3; sole, |K!r- 

 haps 1.50; hand, rather less. Mamma;, three pairs, as in other species. 



Habitat. — Mexico. (Limits of distribution unknown. Not known to 

 occur north of Mexico.) 



Shares wilh G, castanops the single median* furrow of the upjier inci- 

 sors, but is much larger and different in color. The well-prepared speciniiinf 

 here described is only equalled in a large series of G. hursarius by a single 

 much over-stuffed example. The pouches, as well as can be judged from the 

 skin, are smaller proportionally than those of the United Slates species; in 

 this respect being like those of G. hinpiduis. These two Mexican species 

 further agree in the relative smallness of the hands and less enormous devel- 

 opment of the claws ; the fore member being shorter or, at most, not longer 

 than the hinder one. The orifice of the external ear presents, in the dried 

 stale, a mere rim, around which no flap can be fairly recognized. In color, 

 the specimen is not decidedly different from bursarius, though there is a 

 purity of the chestnut-brown which contrasts with the muddy-brown (in 

 some cases almost a glaucous shade or "bloom") commonly seen in bursarius. 

 The fur is deep plumbeous basally, pointed with the warm brown on the 

 u|)per parts, and only partia'ly hidden below by muddy-gray and hoary ends 

 of the hairs. Auricular region darkened. Hind feet and tail mostly whitish. 

 There is some whitishness about the lower jaw, and a small white abdominal 

 and anal patch ; these last being of indeterminate character. The plumbago 

 or "anthracite" variation of pelage occurs in this as in other species of this 

 family. 



* Q. hinpiduB hON been described oh having a Riiigle niiMliao fnrrow ; tho ompbnsis bere, howevnr, is 

 ii)ion "siiiKlo", in uutitboHis to tbe double furrow of G. hurmriuu, witbont reference to exact poxition. 0. 

 i,iza is said to have n "single" furrow; but the proper implication is merely obsoleteness of tbe fine 

 inner second fnrrow naunlly seen. In R. macicanus, as in O. eatlanopa, tbe farrow is truly «injle nnd 

 midiitn ; in G. HnpUlm, single nn<l internal ; in G. tiita, npi^nreiitly single and externnl. 



tNo. '.KM, Mus. Suiitbs. Inst., Xiilapii, Mexico, Dc Oca, 



