JDNE.ISOG.] SYNOPSIS OF THE WEASELS OP NORTH AMERICA. 15 



species (total length from occiput to front of premaxilhio, 28.5; basal 

 length, 26.5; zygomatic breadth, 14; length of palate, 11; interorbital 

 breadth, 5.5; breadth across postorbital processes, 7.5; length of andi- 

 tal bullse, 9.5). The skull is a miniature of P. cicognani except that the 

 postorbital processes are more prominent, the brain case more com- 

 pressed, and there is a distinct sagittal ridge. 



Measurements. Type specimen, female, measured in flesh: Total 

 length, 150; tail vertebra^, 31; hind foot in dry skins, 20-22. 



PUTORIUS ARCTICUS sp. nov. Tundra Weasel. 

 (PL II, figs. 1, la; PL V, figs. 6, 60.) 



Type from Point Barrow, Alaska. No $f flf J $ ad. U. S. Nat. Mus. Collected July 

 16, 1883, by John Murdoch. Original number, 1672. 



Geographic distribution. Arctic coast and tundras. Specimens ex- 

 amined from Anderson Kiver, Franklin Bay, old Fort Good Hope, lower 

 Mackenzie Eiver, Point Barrow, and St. Michaels. 



General characters. Size large; ears small; tail short but with very 

 long black pencil; underparts yellow (including underside of basal half 

 of tail). 



Color (Type specimen, male adult.) Upper parts, including upper 

 lip, dark yellowish brown ; chin white ; under parts deep ochraceous yel- 

 low, broadly including inner and posterior sides of fore legs, whole of 

 fore feet, distal half and inner side of hind feet, and under side of tail 

 to or nearly to black tip; black tip very long, covering at least half of 

 tail (including long terminal hairs); color of upper parts not encroach- 

 ing on belly. In winter pelage, white all over except long black tip of 

 tail; the white tinged with yellow posteriorly. 



Cranial characters. Skull rather large, broad, and massive; frontal 

 very broad interorbitally; muzzle broad and blunt; postorbital proc- 

 esses moderately developed; postorbital constriction marked; zygo- 

 mata strongly bowed outward; brain case subtriangular and rather 

 short; audital bulhe subcylindric; postglenoid space smaller than in 

 richardsoni and hardly inflated except in female. Contrasted with 

 P. richardsoni, the skull of P. arcticus is somewhat larger, much broader, 

 and more massive; brain case subtriangular instead of subcylindric; 

 zygomata bowed far outward instead of appressed; postorbital pro- 

 cesses more prominent; postorbital constriction much deeper; frontal 

 much broader iuterorbitally; palate broader posteriorly; dentition 

 heavier. Adult male skulls of P. arcticus resemble certain old males 

 of ivashingtoni, but differ in much greater breadth of frontal between 

 orbits, broader muzzle, and blunter postorbital processes. P. arcticus 

 resembles true erminea of Sweden much more closely than it does any 

 American species. 



Remarks. Putorius arcticus, which has been heretofore confounded 

 with erminea or richardsoni, is one of the most strongly characterized 

 species of the genus. It is a large animal with deep ochraceous yellow 



