NO. 2 NEW MAMMALS FROM EASTERN PANAMA GOLDMAN 1 3 



Remarks. — Close comparison of this form with the insular species, 

 labilis, is unnecessary, the latter being distinguishable at once by 

 intense rusty reddish coloration. It may he similar to Isothrix 

 caniceps (Giinther), from Medellin, Colombia, but the latter seems 

 to be somewhat different in color, with a bushy tail, and the skull 

 as figured differs in detail. Unfortunately no fully adult examples 

 of the new form are available. In the skull of the type the posterior 

 molars are not yet fully in place. 



Specimens examined. — Two, from localities as follows: 



Panama: Marraganti (type locality), i. 



Canal Zone: Ancon, I. 



SYLVILAGUS GABBI MESSORIUS, subsp. nov. 



Type from Cana (altitude 1.800 feet), in the mountains of ea 

 Panama. No. 179569, male adult, U. S. National Museum (Biologi- 

 cal Survey Collection), collected by E. A. Goldman, May 23, 1912. 

 Original number 21736. 



Genera! characters. — Closely allied to gabbi; general color less 

 rufescent, more grayish or paler huffy, and more heavily overlaid 

 with black. 



Color. — Top of head rust}- reddish mixed with black; nape ochra- 

 ceous buff ; dorsal area varying from buff to pale ochraceous buff 

 of Ridgway, heavily overlaid with black ; sides paler, more creamy 

 buff, the hairs less broadly tipped with black ; nose blackish ; cheeks 

 buffy, more or less washed with black ; ears brownish, becoming 

 blackish along outer side of anterior border ; under side of neck 

 dull buff, this color encroaching on under parts along sides of belly ; 

 rest of under parts, including inner sides of limbs, white, the under 

 color of fur more or less plumbeous across belly ; outer sides of 

 forearms and feet ochraceous buffy; tail ochraceous huffy, with a 

 partially concealed dark spot near tip. Young (in first pelage) : 

 Less rufescent than gabbi or trnei of similar age. 



Skull. — Closely resembling that of gabbi; audital bullae slightly 

 larger, with a correspondingly deeper constriction of basioccipital 

 between them. Compared with that of trnei the skull is less massive, 

 with smaller audital bulla; and decidedly longer palatal bridge. 



Measurements. — Type: Total length, 370 mm.; tail vertebrae, 

 17; hind foot, 80. Average of two adult topotypes : 363 (343-384) ; 

 17 (16-18); 76 (75-78). Skull (type): Greatest length, y^\ con- 

 dylobasal length, 65.5; zygomatic breadth, 36.7; nasals, 29.2 x 12.5 ; 

 interorbital breadth, 15 ; palatal length, 31.2 : length of palatal bri< 

 7.6; maxillary tooth row, 14.7. 



