1888.] NATURAL SCIENCES OF PHILADELPHIA. 97 



patch surrounds one eye and includes one or both ears. Such are fox 

 terriers, bull terriers and bull dogs. The two patches of circumpal- 

 pebral black may interrupt the dorsi-facial white stripe as is seen 

 occasionally in the beagle. 



Both the eyelids and the auricle may be included in the same patch 

 of black as is seen in many dogs especially in pointers. The same 

 is noticed in the Japanese dog. This disposition leads the observer 

 to note that the same black patch may extend still farther backward 

 and be found on the sides of the body. A typical example of such 

 an arrangement is seen in Myrmecoj^haga jubata. In Myrmccohius- 

 the circle extends backward in a stripe. I have seen a similar stripe 

 in the Scotch collie. In Procyon the patch is for the most part in- 

 fra-orbital and extends backward to include the ear. In one of the 

 many varieties of Mephitis the ear and auricle are included in a 

 line of black, while the rest of the head is furnished with white lon- 

 gitudinal stripes ; more commonly, however, the entire head is black 

 exce])t a jugal stri})e which is white and extends down on the side.s 

 of the trunk but inclining toward the dorsum as in Myrmecophaga. 

 When the auricle is black the tip may be furnished Avith a pencil of 

 white hairs which suggest the reversion to the plan of coloration de- 

 scribed on page 88. 



The region of the nostrils or the muzzle is pigmented black in 

 most mammals an exception being found in the Quadrumana as in 

 Semnonith ecus nasalis. 



It is interesting to find that in the bull terrier the black may dis- 

 appear in whole or in part from the muzzle. 



The special organs containing as they do black pigment often ap- 

 pear to determine retention points of the same color at the periphery. 



The breaks in the circumpalpebral color determine the disappear- 

 ance of the color from the region in hairless animals excepting the 

 brov/ where it is apparently caused by the presence at that point of 

 the circumorbital wart. The eyebrow in man is in reality a stripe 

 which tends to pass backward in obedience to the tendency of the 

 stripe in animals generally. 



But the direction taken by the eyebrow is not a guide to all the 

 transitions in the form of the black about the eyes. A vertical 

 black stripe extends from the eye to the mouth in the cheetah ( Cyn- 

 cblurus jnhntus). The same patch includes the lip in some New 

 Foundland and pointer dogs. 



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