44 Mcrriam Two New Marine ()]><>xxiimsfrom Mexico. 



Color. Upper parts from just behind eyes to base of tail dark sepia 

 brown (almost dusky in fresh pelage) ; under parts buffy yellow, much 

 deeper than in canescens ; median face patch (from nose to behind eyes) 

 pale buffy brown ; orbital rings large and black, connected posteriorly by 

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

 tail bicolor, dark above, whitish beneath. 



Cranial characters. Skull and teeth 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 breadth, 4.8; greatest breadth of frontals, 8. 



Remarks. Marmosa oaxacse is an upland or Sonoran representative of 

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

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

 collected by 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 Amolac, Puebla. 



Marmosa oaxacse, on the other hand, inhabits the Sonoran highlands of 

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

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

 Sonoran fauna passes into the tropical, but no evidences of intergradation 

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

 and CJoldman. The new species 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 ; 

 hind foot, 18. 



Marmosa murina mexicana subsp. nov. 



Type from Juquila, Oaxaca. No. 71526, $ im., U. S. National Museum, 

 Biological Survey collection. Collected February 28, 1895, by E. W. Nel 

 son and E. A. Goldman. Original No. 7571. 



Geographic distribution. Southern Mexico, in States of Oaxaca and 

 Chiapas. 



General c-Jiaracters. Similar to M. murina, but rufous of upper parts de 

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

 buffy [in true murina the rufous reaches forward to nose] ; ears smaller. 



Color. Upper parts from between eyes posteriorly to base of tail cin 

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

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

 fro:n end of nose to between centers of eyes buffy, in marked contrast to 

 rufous of top of head. 



Cranial characters. Skull similar to that of M. murina, but interparietal 

 broader and shorter. 



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

 162; hind foot, 20. An adult male from Chicharras, Chiapas: total 

 length, 330; tail, 186; hind foot, 24. 



