DESCRIPTIONS OF TWELVE NEW SPECIES AND SUB- 

 SPECIES OF MAMMALS FROM PANAMA' 

 By E. a. GOLDMAN 



In the early part of 191 1 a collection of 368 mammals was made 

 by me while engaged in the biological survey of the Canal Zone, 

 and adjacent parts of Panama, undertaken by the Sm.ithsonian Insti- 

 tution in cooperation with several government departments, includ- 

 ing the War Department and the Department of Agriculture. This 

 collection, representing- between 40 and 50 genera, includes 12 new 

 species and subspecies which are here published in advance of a 

 general report on the mammals of the region. Nine of the new 

 forms are from the Canal Zone, and the others were taken while 

 on a visit, in March, to the mountains near the headwaters of the 

 Chagres River. 



Acknowledgments are due, especially, to Col. George. W. Goeth- 

 als, LT. S. Army, and others connected with the administration of 

 the Canal Zone, who aided materially in the prosecution of the work 

 of the survey. I am also indebted to Dr. J. A. Allen for the privilege 

 of making comparisons with types and other material in the Ameri- 

 can Museum of Natural History, and to Mr. Samuel Henshaw for 

 the loan of specimens from the Bangs Collection in the Museum of 

 Comparative Zoology. 



MARMOSA ISTHMICA, sp. nov. 



Type from Rio Indio, near Gatun. Canal Zone, Panama. No. 

 170969, male adult, U. S. National Museum (Biological Survey 

 Collection), collected by E. A. Goldman, February 16, 191 1. Origi- 

 nal number 20889. 



General characters.— S\ze large, about as in cliapmani and rua- 

 tanica, larger than mexicana, seledoni or niitis; color about as ni 

 chapmani,\x\t skull with narrower rostrum, slightly smaller teeth. 

 and decidedlv smaller audital processes of alisphenoids. 



Co/or.— General color of upper parts brownish cinnamon, lighter 

 on middle of face, and becoming dull ochraceous buff on sides of 



^This paper is the sixth dealing with the results of the Smithsonian 

 Biological Survey of the Panama Canal Zone. 



Smithsonian Miscellaneous Collections, Vol. 56, No. 36 



