MERRIAM: THE FAUNA OF RANCHO LA BREA. 241 



slightly concave at this point. In the type specimen the enamel has been 

 almost entirely broken away from the outer and posterior sides of the metacone ; 

 and as the extension of the cingulum around the postero-external angle of the 

 tooth is largely removed, the border appears unnaturally straight. In a few 

 California specimens the posterior border is almost as straight with the pos- 

 tero-external portion of the cingulum present as it now appears in the type 

 specimen with the enamel absent from this region. 



In the type specimen the cingulum of the anterior side of the paracone of 

 M 1 appears relatively weak owing to the breaking away of the enamel imme- 

 diately above the lower border of the cingulum. Judging from its sharp 

 inferior ridge, the cingulum in this region was fully as strongly developed 

 originally as in the Rancho La Brea specimens. 



In Leidy's description attention is called to the greater abruptness of the 

 external portion of the basal ridge or cingulum than in the Recent wolves. In 

 the type specimen the external portion of the cingulum of M 1 is marked by 

 a fairly sharp ridge extending along the base of the paracone. This ridge is 

 better developed than in most of the large modern wolves, and the inferior 

 side of that portion of the cingulum bordering the posterior part of the base 

 of the paracone forms a somewhat sharper ridge than in the average of the 

 Rancho La Brea specimens. In some of the California specimens, however, 

 the form and strength of the external cingulum correspond quite closely to what 

 we see in the type. 



The form of M 2 in the type does not differ materially from that in the 

 California specimens. The anterior end of the hypocone is extended around 

 the inner and anterior side of the protocone, whereas in many of the Calif omia 

 specimens it is interrupted on the antero-internal region of the tooth. There 

 are, however, a number of individuals from Rancho La Brea in which pre- 

 cisely the relations shown here are exhibited. In this tooth the metacone 

 appears to approach the size of the paracone rather more closely than in most 

 of the California specimens. The enamel being removed from both tubercles, 

 it would be unsafe to accept the relative dimensions as certainly representing 

 the true external form. Moreover, some of the Rancho La Brea specimens 

 show practically the same relative dimensions of paracone and metacone as 

 appear in M 2 of the type specimen. 



The superior carnassial of the type is badly broken, and shows nothing 

 of the protocone blade. The antero-internal root does not extend far in toward 

 the median line, indicating a small deuterocone as in the California specimens. 



The form of P 2 and P 3 of the type is closely similar to that of the California 

 specimens. The extraordinarily strong internal cingula and the strong antero- 

 internal ridges which Leidy mentions as occurring on these teeth in the type 

 are noticed also in most of the Rancho La Brea specimens. 



The form of the maxillary bone of the type is not noticeably different from, 

 that in the California species, excepting that the superior border of the infra- 



