30 MERRIAM 



Characters. — External characters unknown. 



Cranial characters. — Skull large; nasals long and slender; pos- 

 terior part of mandible large. Compared with typical americanus 

 from Ungava, Hudson Strait, the skull of dalli is very much larger 

 (basal length 65 mm. or more instead of 61 or less) : rostrum, nasals, 

 and incisive vacuity decidedly longer; jugal longer and somewhat 

 broader (vertically) ; mandible very much larger and more expanded 

 posteriorly ; molariform teeth larger. 



Remarks. — Superficially the skull of dalli resembles that of sub- 

 species virginianus from Ossipee, New Hampshire, much more 

 closely than typical americanus ; the agreement in size is better and 

 both have rather long, slender nasals. But dalli has a much broader 

 braincase, longer and heavier zygomata, broader jugals, and differs 

 in other particulars. Compared with its geographical neighbor, L. 

 macfarlani from Fort Anderson, it may be distinguished at a gltmce 

 by its slender nasals and rostrum, longer zygomata, and larger 

 mandible. 



Cranial fneasurements. — Type skull : Basal length 65 ; zygo- 

 matic breadth anteriorly 37.5 ; at middle 38 ; postpalatal length 33.5 ; 

 frontal breadth across middle of postorbital processes 21 ; breadth of 

 nasals posteriorly 15; anteriorly 11. 



LEPUS AMERICANUS MACFARLANI subsp. nov. 

 MacFarlane Varying Hare. 



Type (skull) from Fort Anderson, north of Great Bear Lake, Arctic 



America. No. 14467 U. S. National Museum. R. MacFarlane. 



Characters. — External characters unknown. 



Cranial characters. — Skull similar to that of typical americanus 

 from Hudson Strait but ver}' much larger and heavier; nasals very 

 broad (anteriorly as well as posteriorly); braincase less flattened; 

 supraoccipital shield narrower and tapering posteriorly; mandible, 

 molariform teeth, and lower incisors decidedly larger. Compared 

 with dalli from Nulato River the nasals are very much broader and 

 blunter; rostrum broader and more massive ; braincase higher (almost 

 ridged along median line) and much less ikittcned ; supraoccipital 

 shield narrower posteriorly (more tapering) ; mantlible somewhat 

 smaller. 



Cranial measurements. — Basal length 67; zygomatic breadth an- 

 teriorly 38.5; at middle 41 ; postpalatal length 34.5; frontal breadth 

 across middle of postorbital processes 21; breadth ot" nasals pos- 

 teriorly i7-5) anteriorly 14. 



