1879.] NATURAL SCIENCES OF PHILADELPHIA. 181 



the brain case. The zygoma is rather slender, is elongate, and 

 but little expanded. The otic bullae are very large ; the paroccipi- 

 tal processes are directed backwards, at an angle of 45, and are 

 rather elongate and acute ; they cap the bullae posteriorly. The 

 lateral occipital crests bound a fossa of the occipital region near 

 the condyles. The occipital surface is directed horizontally back- 

 wards ahove the foramen magnum. This part of it, and its supe- 

 rior portion, are divided by a median keel. 



The basioccipital is keeled on the middle line below. The 

 sphenoid is not keeled, and is concave, its borders descending on 

 the inner side of the bullae. The ptei\ygoid fossa is rather narrow, 

 and the hamular process is short. The posterior border of the 

 palate does not extend anterior to the posterior edges of the last 

 tubercular molar, and its middle portion projects backwards in a 

 triangular process. The palatine fossa for the inferior sectorial 

 is shallow. The superior surface of the postorbital region is 

 roughened. 



The foramen infraorbitale exterius is rather large, and issues 

 above the anterior border of the sectorial tooth. The f. incixiva 

 are short, not extending posterior to the middle of the canines. 

 The /. palatina are opposite the posterior border of the sectorial. 

 The/, lachrymale is altogether within the orbital border. The/. 

 opticum is rather large. This species is peculiar in having the' 

 /. /. spheno-orbitale, rotundum, and alisph enoidale anterius united 

 into one large external orifice. The alisphenoid canal is larger in 

 Canis latrans, and its posterior foramen small. The /. ovale is 

 further removed from the/, alisphenoidale than in the coyote, and 

 is exterior to and a little behind the/, carotideum. 



The nasal bones extend to above the middles of the orbits, and 

 contract gradually to their apex. Their combined anterior border 

 is a regular concave, and the lateral angles at this point are pro- 

 duced outwards and forwards. The posterior apex of the pre- 

 maxillary bone is separated from the anterior apex of the frontal 

 by a short space. The maxillo-malar suture is deeply notched in 

 front below, and it extends upwards to above the infra-orbital 

 foramen. A very narrow surface of the lachrymal is exposed on 

 the external surface. The pterygoid bone is distinct, and is nearly 

 equally bounded by the sphenoid and palatine on the outer side. 

 The inferior suture of the orbito-sphenoid runs in a groove, which 

 is deepest anteriorly. 



