South- American Muridse. 499 



Skull large and heavily built. Nasals long, slightly con- 

 stricted about the middle, evenly tapering backwards, neither 

 so long nor so narrow as in N. apicalis. Frontal flattened ; 

 supraorbital edges evenly divergent, straight, not bowed 

 until they have reached the parietals ; fronto- parietal suture 

 forming nearly a right angle at the centre, instead of being 

 nearly transverse. Palatal foramina parallel-sided, not 

 broader behind than in front. Posterior edge of palate square. 



Dimensions of the type (an adult male measured in skin) : — 



Head and body (c") 2>J0 ; tail (c.) 270; hind foot (mois- 

 tened) 56; length of last foot-pad 11. 



Skull, see p. 500. 



Hah. Concordia, Medellin, Colombia. Coll. J. K. Salmon. 



Type. B.M. 73. 11. 5. 3. 



Nectomys magdalencBj sp. n. 



External characters unknown. 



Skull heavy, rounded, its upper profile evenly convex 

 throughout, and the frontal and parietal regions markedly 

 swollen ; this uniform convexity gives the skull a very dif- 

 ferent appearance to the frontally flattened skulls of other 

 species. Nasals fairly broad, slightly compressed about their 

 middle, pointed behind, but not markedly produced backwards. 

 Line of supraorbital ridges slightly curving as they diverge, 

 the curve evenly continuous with that of the temporal ridges. 

 Fronto-parietal suture almost directly transverse. Inter- 

 parietal rather longer antero- posteriorly and narrower trans- 

 versely than usual. Anterior palatine foramina well open, 

 parallel-sided, rounded at their ends. Posterior palate with 

 the lateral pits unusually large and deep ; palatal margin 

 square. 



Dimensions, see p. 500. 



Hab. W. Cundinamarca, in lowlands near Magdalena R. 

 Type. B.M. 97. 3. 17. 1. 



Nectomys fuIvtnuSf sp. n. 



Fur unusually short, the hairs only about 10-11 millim. In 

 length on the back. General colour fulvous, lined with brown 

 on the middle of the back, rather clearer on sides, and con- 

 tinued into the paler fulvous of the belly. Wool-hairs short 

 and close, slaty grey basally, their tips fulvous above, buffy 

 or whitish below. Hands and feet thinly haired, pale brown. 

 Tail-hairs uniformly brown. 



Nasals long, contracted at half their length, less attenuated 

 and drawn out than in iV. ajncalis. Interorbital region flat, 



