170 T)R. E. KAT LANKESTER ON THE 



longer tlian the other. Much more striking are the differences at the proximal end oC 

 the hinder surface. Here the area between the head and the two trochanters is narrow 

 and uneven ; the trochanters themselves are closely approximated and connected with one 

 another by an oblique ridge ; while the lesser trochanter is relatively larger and situated 

 on the posterior surface of the shaft considerubly behind its preaxial border, so as to be 

 almost entirely concealed w^hen the bone is viewed from in front. 



In a distal view of the femora of ^J^luropiis, ^Elnrus, and Procyon the two condyles 

 have their posterior borders nearly in the same vertical plane, whereas in Vrsus the innc^r 

 condyle projects nearly half an inch behind the plane of the posterior border of the outer 

 one. 



Tiie evidence of this bone is therefore very strongly in favour of an intimate connec- 

 tion between the three genei'a first named and their wide differences from the fourth. 



The tibia and fibula of u3^lunis correspond with the femur in relative shortness and 

 stoutness. In the tibia the ligament by which the patella is attached springs from a 

 separate ossification of the proximal epiphysis, as is the case in Bears and many other 

 mammals. Perhaps, in addition to its general proportions, the most distinctive feature 

 of this bone is the extreme shallowness of the groove on its distal surface for articulation 

 with the astragalus. In this respect it closely accords with the larger and moi-e slender 

 tibia o^ ^-Elur^is, but differs widely from Vrsus. In Procyon, the tibia is to some extent 

 intermediate between these two types. As regards the fibula, it will suffice to say that 

 in both ^Eluropns and ^lElurits it is characterized by the great expansion of its tw'o 

 extremities. 



In correlation with the shallow "rooves on the distal extremitv of the tibia, the 

 astragalus of ^Eluropns is characterized by the slight elevation of the ridges on its tibial 

 surface, while above that surface it lacks the proiection which is so conspicuous in the 

 corresponding bone of the Bear. Another characteristic feature of the tarsus of the genus 

 under consideration is theantero-posterior elongation of the cuboid — a feature also shared 

 by the tarsus of ^Elurus, but not by that of Ursns, in which the cuboid is transversely 

 elongated. To the inner side of the navicular is articiilated in both ^Eluropus and ^Slurus 

 a very large tibial sesamoid, which is of a pointed form and extends down by the side of 

 the entocuneiform. I cannot find evidence of the existence of this tibial sesamoid in 

 either Procyon or Vrsus. Both ^Elurus and Procyon difftr from ^Eluropus in the greater 

 length and slenderness of the metatarsals, this feature, which is doubtless a fimctional 

 one, being most developed in Procyon. It may be added that the cuboid of the latter 

 genus is of the elongated .^jEJluropus type. 



Prom the loregoing survey it will be evident that, so far as its dentition and osteology 

 are concerned, ^Uluropus is very closely allied to ^Elurus, the resemblance of some 

 of the bones of the two genera being so close as to suggest specific rather than generic 

 distincticm. Prom Vrsus the differences presented by the bones of both genera are 

 very marked ituleed. As regards the American representatives of the Procyonidie, the 

 dental and osteological resemblances presented by the tw^o genera in question are very 

 noticeable, although in some, but by no means all, respects these are greater in ^Murtis 

 than in ^Eluropus. In its retention of the last lower molar the latter serves, indeed, to 

 connect the former with Vrsus, Uycenarcius. Amphicyon, etc. 



