80 NORTH AMERICAN MUSTELID^. 



Measurements of skulls of MM. foina, martes, and Americana. 



M. foina 

 (Germany). 



M. martes 

 (Sweden). 



M. americana 

 (Aladka). 



Total Ipngth 



Greatest width 



Least width (exchisive of muzzle) 



Distance between orbits 



Upper incisors from front hinder margin 

 of palate 



Upper molars and premolars, length taken 

 together 



Lower jaw, leujith, from apex of symphy- 

 sis to back ot condyle 



Lower jaw, height angle to top of coro- 

 noid 



Front border of orbit, end of intermax- 

 illary 



Width of muzzle behind canines 



Greatest length of zygoma 



(rreatest width of palate inside teeth 



Width across supraorbital processes 



Greatest length (longitudinal) of back 

 upper molar 



Width of cranium proper 



Inches. 

 3.25 

 1.85 

 0.80 

 0.85 



1.55 



0.95 



2.05 



0.90 



0.95 

 0.68 

 1.50 



0. S5 



1. dO 



0.2.3 

 1.40 



Inches. 

 3.50 

 1.95 

 0.80 

 0.85 



1.75 



1.10 



2.40 



1.00 



1.10 

 0.70 

 1.65 

 0.90 

 0.95 



0.28 

 1.40 



Inches. 

 3.60 

 1.85 

 0.70 

 0.80 



1.75 



1.10 



2.40 



1.10 



1.10 

 0.70 

 1.70 



0.89 

 0.90 



0.20 

 1.40 



The iiiflications afforded by the foregoiug measuremeuts, together with 

 some other cranial and dental characters, may be snmmed in the following 

 diagnostic paragraphs. It will be seen that most of the cranial points brought 

 out by Prof. Baird {o}). cit. p. 155) are substantiated, but it must be borne 

 iuimind that they are matters of degree, which may not always hold, except 

 of averages. The remarkable difference in the back upper molar, as insisted 

 upon by Gray, is the principal character upon which to rely between martes 

 and americana. 



Comparatire diagnoses. 



M. martes.— luuer moiety of back upper molar one-third longer than outer 

 moiety, and altogether about twice as large (coincidently with which the 

 entire dentelure of w/ar^es is stronger than in the other two forms, though 

 differences in particular teeth are not readily expressed) ; outer border of 

 outer moiety regularly strongly convex. Fang of last upper premolar large, 

 transverse. Penultiiuate under molar with a cusp well developed at the 

 postero-internal base of the main cusp. Sides of muzzle nearly parallel. 

 Supraorbital processes midway between greatest constriction of cranium and 

 anterior root of zygoma ; the constriction moderate. Zygomatic width more 

 than half total length of skull. 



M. americana. — Inner moiety of back upper molar scarcely longer or larger 

 than the outer [in 25 skulls examined] ; outer border of outer moiety double- 

 convex, i e., with an emargination. Fang of last premolar small, oblique. 

 Penultimate under molar with merely a slight heel at base inside of the main 

 cusp. Sides of muzzle sensibly tapering. Supraorbital processes nearer point 

 of greatest constriction than anterior root of zygoma ; constriction great. 

 Zygomatic width about half total length of skull. 



M. foina. — Molar and last upper premolar as in americana; penultimate 

 lower molar with prominent supplementary cusp as in martes. Sides of muz- 

 zle sensibly tapering. Supraorbital processes much nearer point of greatest 

 constriction than anterior root of zygoma; constriction slight. Zygomatic 

 width much more than half total length of skull. 



