CHARACTERS OF THE PROCYONID^. 399 



compressed and pouted in the middle line. The point is not 

 without importance, because all the Ursidse differ from all the 

 Procyonida? and from Ailurus in having the lips protrusible or 

 capable of being pouted. In the Procyonidse and Aihtrtis the 

 lips above and below the incisor teeth are comparatively closely 

 adherent to the gums as in normal Carnivora. 



By the characters supplied by the snout and rhinarium the 

 genera may be classified as follows : — 



a. Snout greatly elongated ; upper edge of rhinarium produced be- 

 yond the nostrils so that its anterior surface is nearly flat and 

 slopes obliquely downwards and backwards ; anterior portion of 

 nostrils vertically elongated, separated by a high, narrow, un- 

 grooved septum, and almost concealed in profile view. Upper 

 lip long and undivided by philtrum Nasua. 



a . Snout not, or only moderately elongated ; upper edge of rhi- 

 narium not produced, its anterior surface ligbtly convex, not 

 noticeably receding; anterior portion of nostrils subcircular, 

 separated by a low, broad, generally grooved septum, and visible 

 in profile view. 



b. Snout moderately produced ; upper lip long so that the width 

 of the rhinarium is less than the combined heights of the 

 rhinarium and upper lip ; median groove on rhinarium weak, 

 or indistinct. 



c. Upper lip undivided by philtrum ; infranarial portion of rhi- 



narium deep and wide, median groove abbreviated or 



indistinct Prooyon. 



c'. Upper lip divided by long, narrow, groove-like philtrum; 

 infranarial portion of rhinarium shallow and narrow, median 



groove complete Bassariscus. 



bK Snout not produced; upper lip short, width of rhinarium ex- 

 ceeding its height from the summit in front to edge of upper 

 lip ; median groove strong. 



d. Infranarial portion of rhinarium very deep. 



e. Philtrum moderately broad Iiassaricyon. 



e' . Philtrum very broad Potos. 



d'. Infranarial portion of rhinarium comparatively shallow and 



philtrum narrow Ailurus. 



By this key Ailuropoda, so far as it is possible to judge, would 

 fall under heading d' alongside Ailurus, from which it differs in 

 having the upper surface of the rhinarium covered with hair. 

 The rhinarium is variable in the Ursidaa, being comparatively 

 highly specialised in Melursus (Ann. Mag. Nat. Hist. (9) i 

 pp. 378-379, 1918). 



The Feet. 



In describing the feet of the American genera, those of Nasua 

 may be taken as a standard for comparison. 



The claws of the fore foot are long, powerful, blunt and not 

 greatly curved, and the digits are united by web, as described by 

 Mivart, up to the proximal end of the digital pads. The under- 

 side of the digits and of the webs is entirely naked. The plantar 

 pad is broad, moderately well defined and four-lobed. Tbe two 

 conjoined carpal pads, of which the outer is about twice as 

 large as the inner, are together as wide as the plantar pad and 



