[From the American Journal of Otology, Vol. L, July, 1879.] 



THE OUTER EAR OF BLARENA BREVICA UDA. 



By DR. ELLIOTT COUES, U.S.A. 



Tins animal lias sometimes been described as having no external 

 ear, and even named technically (" Anotns") from this alleged cir- 

 cumstance ; but the orifice of the external meatus is extremely 

 large, and the folds of skin which constitute an auricle are promi- 

 nent and of remarkably complicated structure. Though the pres- 

 ence of a large auricle is now known, 1 have seen no sufficient 

 description of its structure. On viewing the parts when the fur is 

 undisturbed, no ear whatever appears, because the flap of integu- 

 ment is folded so closely forward as to lie quite smoothly, com- 

 pletely closing the meatus like a valve, and showing only its back 

 surface, which is as densely hairy as the rest of the integument 

 about the ear. But, on pushing or blowing the fur aside, and 

 opening up the parts, the orifice gapes widely ; its longest diameter 

 is a fourth, if not three-tenths, of an inch in extent ; it is oblique 

 in general direction, upward and backward ; the general cavity 

 seems naked, but is really beset with numberless colorless hairs, so 

 minute as to be invisible except under the lens. In advance of 

 this closely pilous surface is a somewhat crescentic margin of abso- 

 lutely naked skin, with the outer border of which latter the common 

 furry integument of the head is continuous, without a trace of a 

 raised rim. This naked crescentic strip is that against which the 

 border of the flap of the ear is applied, fitting closely. At the 

 back of the pilous surface certain folds of naked integument rise 

 to meet the- attached base of the auricle, and another such fold 

 curves around the true orifice of the meatus externus, circumscrib- 

 ing this aperture posteriori}-. Anteriorly it is circumscribed still 

 more conspicuously by a fold of the common integument. The 

 meatus itself is a nearly circular opening, at least a tenth of an 

 inch in diameter, situate at the bottom of the general cavity I am 



