NO. 36 NEW MAMMALS FROM PANAMA — GOLDMAN 3 



Measurements. — Type : Total length, 597 mm. ; tail vertebrae, 332 ; 

 hind foot, 48. Skull (type): Greatest length, 63; condylobasal 

 length, 61.7; zygomatic breadth, 31.7; nasals 30 x 9.5; interorbital 

 breadth, 9.3 ; palatal length, 34.5 ; upper molariform toothrow, 22,2. 



Remarks. — In Panama this form seems to be a much rarer animal 

 than M. fuscogriseus, which occurs at the same localities and seems 

 to have similar habits. A specimen taken at .2500 feet elevation on 

 Cerro Azul, near the headwaters of the Chagres River is like those 

 from near sea level at Gatun. 



Specimens examined. — Total number, 4, from localities as follows : 



Canal Zone: Gatun (type locality), 2. 



Panama: Cerro Azul, i. 



Costa Rica: Angostura, i. 



SCIURUS VARIEGATOIDES HELVEOLUS, subsp. nov. 



Type from Corozal, Canal Zone, Panama. No. 17 1540, male adult, 

 U. S. National Museum (Biological Survey Collection), collected 

 by E. A. Goldman, June 15, 191 1. Original number 21166. 



General characters. — Similar in general to dorsalis and variega- 

 toides, but limbs and under parts paler in the grizzled-back phase ; 

 premolars \ (premolars f in dorsalis). 



Color. — Phase with grizzled back : Top of head and back mixed 

 black and pale bufif, the mixture producing a grizzled effect; 

 muzzle and sides of head buffy grayish, much paler than top of 

 head; under parts and limbs pale buff, the color richest on outer 

 sides of forearms, along flanks and on lower base of tail, becoming 

 somewhat paler on feet; ears broadly edged with black anteriorly, 

 more narrowly posteriorly, the ear patches pale buff or white, tail 

 above at base like back, rest of upper side black and white, the hairs 

 broadly tipped with the latter color, below varying along median 

 hne from pale ochraceous buff to pale cinnamon-rufous, bordered 

 with black and edged with white. Variation: One specimen in 

 worn pelage, perhaps representing the black-backed phase seen in 

 dorsalis, has the under parts and limbs uniform pale buffy gray, and 

 the top of head and back blackish in patches. The top of head and 

 back are more uniform in color, and the dark dorsal area broader 

 than in typical examples of dorsalis in this phase. 



Measurements.— Type: Total length, 508 mm.; tail vertebras, 

 255 • hind foot, 63. An adult topotype : 540 ; 274 ; 67. Skull (type) : 

 Greatest length, 577; condylobasal length, 53; zygomatic breadth, 

 34.2; nasals, 19.3; interorbital breadth, 21; palatal length, 26.7; 

 maxi'uary toothrow (small anterior premolar absent), 10.7. 



