44 3Irrrl«iiii — Two Nciv Murhic Opos^inii>< from Mexico. 



Color. — Upper i)art8 from just bcliind t^ves t(i ])ase of tail dark sepia 

 brown I almost dusky in fresh pelage); under parts ])utly yellow, murh 

 deeper than in raufxceiiK ; median fiiee i)atch (from no.se to ))ehin(l eyes) 

 l)ale buti'y brown ; orbital rings large and black, connected posteriorly by 

 dark top of head ; dark color of upper parts reaching wrists and ankles ; 

 tail l)icolor, dark ul)ove, whitish beneath. 



Craitialchardders. — Skull and teetli similar to those of D. canescens, but 

 frontal plate a little broader. Measurements of skull of type specimen : 

 basal length, 29; zygomatic breadth, 18.5; palatal length, 17; interor- 

 bital bi-eadth, 4.8; greatest breadth of frontals, 8. 



lieiiiarks. — Marmosa cxtxaac is an upland or Sonoran representative of 

 the tropical M. canescens of J. A. Allen. The type o{ cuncscens came from 

 Santo Domingo de Guzman, on the Isthmus of Tehuantepec. Specimens 

 collected b}' Mr. Nelson extend its range northwesterly over the arid 

 tropical hills and lowlands of the States of Oaxaca, Guerrero, and Micho- 

 acan to the Hacienda Magdalena, in Colima. A specimen was obtained 

 as far inland as Ainolac, Puebla. 



Marmosa oaxac:^, on the other hand, inhal)its the Sonoran highlands of 

 Oaxaca, at the extreme southern end of the tableland of ^Mexico — a very 

 different fauna. The two forms may he found to intergrade where the 

 Sonoran fauna passes into the tro[)ical, but no evidences of intergradation 

 are to be seen in the eleven specimens of canescens obtained by Nelson 

 and Goldman. The new s])ecies rests on two specimens — the type, an 

 old female, and an immature male — both from Oaxaca 



Measurements (of type specimen in flesh). ^Total length, 263 ; tail, 144 ; 

 bind foot, IS. 



Marmosa murina mexicana subsp. nov. 



Ti/pe from Juquila, Oaxaca. No. 71526, c? im., U. S. National Museum, 

 Biological Survey collection. Collected Februai-y 28, 1895, by E. W. Nel- 

 son and E. A. Goldman. Oi-iginal No. 7571. 



(h'oi/rapliic ili^lrihntidii. — Southern Mexico, in States of Oaxaca and 

 Chiapas. 



General clnirurlirx. — Similar to M. murina, but rufous of upper parts de- 

 cidedly paler, and middle of face from between eyes to nose abruptly 

 Imtfy [in true nmrina the rufous reaches forward to nose] ; eai'S smaller. 



Color. — Upper parts from l)etween eyes posteriorly to base of tail cin- 

 namon rufous, gradually fading on sides to ochraceous huffy on belly ; 

 orbital ring black and reaching anteriorly to whiskers; middle of face 

 fro;n end of nose to between centers of eyes bufty, in marked contrast to 

 rufous of top of head. 



Cranial cliaraclers. — Skull similar to that of 3/. marina, but interparietal 

 l)roader and shorter. 



Measnrenients. — Type specimen (not full grown) : total length, 274 ; tail, 

 162; hind foot, 20. An adult male from Chicharras, Clnai)as : total 

 length, ;].■)(); tail, 186; hind foot, 24. 



