Ko. 2333. MAMMALIA COLLECTED IN PERU BY HELLER— THOMAS. 245 



Coenolestes. First premolar minute, perhaps one fifth to one tenth 

 the bulk of the second, its tip not or barely as high as the cingular 

 cusp of the canine ; in Coenolestes the first and second premolars are 

 subequal, sometimes one and sometimes the other slightly the larger. 

 P3 (the sector or pm* of the catalogue) of about the same size as in 

 Coenolestes, its thickness transversely subequal anteriorly and poste- 

 riorly, while in Coenolestes it is thicker behind than in front, as is 

 more usual in marsupials generally. Molariform teeth (p* and 

 molars) as in Coenolestes, the minute m^ perhaps averaging even 

 smaller. 



Lower teeth more like those of Coenolestes than is the case with 

 the upper, but there is a corresponding, though slighter, reduction 

 in the relative size of the posterior incisors, the canine and anterior 

 premolars. 



As a genus this animal is most readily distinguishable from 

 Coenolestes by the shortening and the double-rooted condition of 

 the upper canines, and the reduction in the relative size of p\ 



Specific characters.— E^iQTniiWy hardly distinguishable from 

 Coenolestes fuliginosus, being of the same size and proportions, and 

 of the same dull grayish-brown (near " clove-brown ") color above, 

 C. olsGurus being more strongly brown in tone, though this difference 

 may possibly be due to the fading of the specimens of the latter. 

 Undersurf ace paler brown, the ends of the hairs drabby brown ; in 

 C. fuUginosus the ends of the belly hairs are dull grayish white. 

 Ears with a narrow rim of whitish or glossy hairs, this whitish rim 

 not perceptible in the specimens of Coenolestes. Hands and feet 

 brown on metapodials, lighter on digits. Tail averaging about the 

 length of the head and body, thinly haired, either uniformly dull 

 brown or slightly mottled with dull whitish. 



Skull and teeth as described above. 



Dimensions of four specimens : Male 194401 (type) , head and body, 

 120; tail, 108; hindfoot, 22; ear, 15. Male 194381, head and body, 

 122; tail, 113; hindfoot, 22.5; ear, 15. Female 194397, head and 

 body, lOG; tail, 104; hindfoot, 21.5; ear, 15. Female 194398, head 

 and body, 105; tail, 125; hindfoot, 22.5; ear, 15. 



Skulls of male and female, the first the type : Greatest length, 33, 

 31.4; condylobasal length, 32.5, 31; zygomatic breadth, 14.8, 14.8; 

 nasal length, 17.5, 15.6 ; intertemporal breadth, 7.8, 7.8 ; breadth of 

 brain case, 12.4, 12 ; palatal length, 19, 18 ; palatal foramina, 7.3, 7 ; 

 upper tooth series, 18.3, 17.5; combined length of three anterior 

 molariform teeth (p* to m-), 5.4, 5.3; lower tooth series, 17. 16.6; 

 length of ii, 5.2, 4.9 ; three anterior lower molariform teeth, 5.8, 5.8. 

 Type.— Kdiwlt male from Torontoy. U.S.N.M., No. 194401. Origi- 

 nal No. 248. Collected May 14, 1915. 

 Seventeen specimens as follows: 



