272 NORTH AMERICAN MUSTELID^ 



proximately parallel — more nearly so than usual in this family. 

 The spread of the zygomata is rather more than three-fifths 

 the total length of the skull; the outward curvature is greatest 

 behiud. The great width of the skull behind leaves a very 

 broad basilar space, notwithstanding the size of the bulhe. 

 This space narrows but little as it advances between the ptery- 

 goids, and is nearly liat throughout. A curious character is 

 seen in the division of the posterior nares into two by a ver- 

 tical bony septum running to the very edge of the palate, and 

 thence projecting into view. Skunks and Land Otters have 

 such a septum, but it is not complete to the end of the bony 

 l^alate. In the Sea Otter, it is represented by a lamina depend- 

 ing from the roof of the nares, but not reaching the palate for 

 about an inch from the end of the latter. In the Martens, 

 Weasels, and Wolverene {MusteUnw)^ there is nothing whatever 

 of the kind. The pterygoids are simply laminar, with some 

 little irregularity outside, as usual ; they are moderately hamu- 

 late. The (comparatively) immense inflation of the large bullje 

 occupies nearly all the extent of the periotic bones ; the swell- 

 ing is immediate all along the interior border; outwardly it 

 subsides in a moderately tubular meatus, and behind it is re- 

 placed by a concavity around the foramen. 



The mandible is massive; the ramus lower and thicker before 

 than behind; the symphysis long, strong, aijd early completed; 

 the coronoid low and of peculiar shape. Its apex is obtuse ; its 

 front border nearly straight, but its hinder border divided at 

 an abrupt angle into a lower perpendicular part and an upper 

 strongly oblique portion. The lower border of the ramils is a 

 gentle curve along the symphyseal portion, thence a straight 

 line to a considerable angle abreast of the last molar, thence 

 straight again to the proper angle of the jaw, which is small 

 and not at all exflected. In young animals, the same border is 

 more nearly a continuous slight curve from symphysis to the 

 end. The condyle is very broadly transverse ; its articular sur- 

 face is extensive, with a peculiar twist to correspond with the 

 above described formation of the glenoid fossa. 



A young animal should be examined with reference to the 

 teeth, as the characters of the molars become much obscured 

 by wear. The back upper molar is neither narrowly transverse 

 as in the Martens and Weasels, nor cxuadrate as in the Skunks 

 and Otters, but triangular; and in size and shape it is not very 

 dissimilar to the last premolar. Details aside, it is a right-an- 



