No. 3.] 



ALLEN ON THE GENUS BASSAEIS. 



witli a wasli of black of variable amount, proclnccd by tbe black tips ox tlic louger 

 hairs, usually strongest along tlie middle of the back ; below -wliitisli, tinged more or 

 less strongly Avith j)ale yellow. Eyes naixowly encircled with brownish-black. 

 Behind and above each eye a large, sometimes rather indistinct, spot of yellowish- 

 gray, and a smaller spot of the same color below each eye. Tail with alternating 

 rings of white or grayish-white and black, and black at the tip. The usual number 

 of rings of either color varies from 7 to 9. The females are considerably smaller than 

 the males. 



J>. astuta. B. sumiclirastL 



Ears rather narrow and pointed. Soles 

 and pahns with short soft hair on the 

 edges and at the base of the toes between 

 the naked pads. 



Upper surface of the feet slightly or not 

 at all blackish. 



Light rings of the tail broad, pure white, 

 or sometimes slightly grayish- or yellowish- 

 white, nearly as broad as the intervening 

 black ones. The black rings are divided 

 below by a more or less broad mesial band 

 of white, running nearly the whole length 

 of the tail, the lower surface of which is 

 white, broadly scalloped on the edges 

 with black. 



Anterior surface of upper incisors 

 smooth, the cutting-edge even. 



First ui)per molar with both limbs 

 longer and narrower than in B. sumiclirasti, 

 the inner with two distinct cusps, and 

 another on the posterior outer edge of the 

 tooth. 



Second upper molar with the transverse 

 diameter, compared with the antero-pos- 

 terior, relatively greater than in B. sumi- 

 clirasti. 



Last lower premolar with a small acces- 

 sory cusp on the posterior border. 



Canines and whole dental armature 

 relatively weaker, the molars narrower, 

 and their cusps sharper and more numer- 

 ous than in B. sumiclirasti, in specimens 

 of corresponding ages and degree of attri- 

 tion of the teeth. 



Auditory bullte strongly inflated, spheri- 

 cal, the meatus auditorius very large. 



Size less than in B. sumiclirasti. Length 

 of head and body 14 in. ( J ) to 17 in. ( <? ) ; 

 tail-vertebrte about 12 to 15 ; tail to end of 

 hairs about equal to length of head and 

 body. Skull, length 3.00 to 3.25; width 

 L.85 to 2.05. 



Ears broader and shorter, absolutely as 

 well as relatively, and less pointed. Soles 

 and j)alm8 wholly naked. 



Upper surface of the feet black or black- 

 ish, and general color of dorsal surface 

 usuallj'^ darker than in B. astuta. 



Light rings of the tail narrow, gray, 

 sometimes tinged with brownish. The 

 black rings are much broader than the 

 alternating white ones, unbroken, com- 

 pletely encircling the tail, the lower sur- 

 face of the tail scarcely dilfering in color 

 fi'oni the upper. 



Anterior surface of the upper incisors 

 with two slight longitudina! groiives deep- 

 ening ai^ically, ijroducing a distinctly 

 crenulated cutting-edge. 



First upper molar shorter and thicker 

 than in B. astuta, with -no accessory cusp 

 on the posterior outer corner, and lacking 

 that seen on inner anterior angle of the 

 tooth in B. astuta. 



Second upper molar heavier than in B. 

 astuta, with a relatively shorter transverse 

 diameter. 



Last lower premolar Avith no accessory 

 cusp on the j)osterior border. 



Auditory bullae less swollen, flattened 

 on the posterior inner face, with a much 

 smaller meatus auditorius. 



Size larger. Leugth of head and body 

 15i iu. ( 5 ) to 19^ ill. ( c^ ) ; tail-vertebrie 

 16 to 20; tail to end of hairs 1« to 22. 

 Skull, length 3.25 to 3.G0 ; width 2.25 to 

 2.50. 



