CHARACTERS OF THE PROCYONIDvE. 419 



Procyon I possess*. Further on we read : "A point of resemblance 

 between Ursus f and sEluropus is to be found in the circumstance 

 that the maxillary [preorbital] foramen opens on the side of the 

 skull well in advance of the zygomatic root, whereas in JElurus 

 and Procyon it perforates the zygoma itself." So far as this 

 statement is applied to the Ursidae, it is contradicted by the 

 Malayan Bear, in which the foramen perforates the zygoma exactly 

 as in Ailiirus and all the American Procyonidse. I may also add, 

 in this short-headed species of Ursidae the zygomatic width of the 

 skull bears to the basal length about the same proportion as in 

 Ailuropoda, thus contradicting Lankester's statement that " in all 

 Bears the skull is much longer and narrower both in its facial 

 and cranial regions than in the skull of yEluropus.'' Bardenfieth 

 similarly wrongly contrasts Jiluropus with Ursus when he says 

 of the former " zygomatic arches exceedingly wide " and of the 

 latter " zygomatic arches moderately wide " ; and his statements 

 that the basioccipital is broad and the bulla not inflated in Ursus 

 are not always true of the species in question. These cor- 

 rections, however, are of no great moment in settling the degree 

 of kinship between the Ursida?, Ailuropoda, and Ailurus — the 

 point at issue between the authors quoted. What they prove is 

 that the resemblances between the genera concerned are closer 

 than either author claimed. 



My own opinion about the matter is that Lankester and 

 Lydekker, as Bardentieth held, overrated the resemblances be- 

 tween Ailuropoda and Ailurus and underrated the differences ; 

 and that Bardenfieth underrated the peculiarities of Ailuropoda 

 which distinguish it from the Ursidse. The attempt to place 

 Ailuropoda in the Procyonidse makes the definition of that family 

 an impossibility. For example, every character used by Lydekker 

 for defining that family has its exception. The same criticism 

 cannot be advanced against its inclusion in the Ursidse, because in 

 one or two well-marked characters, like the structure of the feet, 

 the length of the tail, and the presence of m. 3 in the mandible, 

 Ailuropoda and the genera of Ursidse resemble each other, and 

 differ from Ailurus and the American genera assigned to the 

 Procyonidne. But since the assignment of Ailuropoda to the 

 Ursida? disturbs the homogeneity of that family, which already 

 has some half-dozen well-defined genera, I prefer to regard 

 Ailuropoda as the representative of a distinct family. The genus 

 is neither Ursid nor Procyonid, but something distinct from 

 both. 



* Bardenfieth also is wrong in stating that llelursus is without frontal post- 

 orbital processes. 



f Fig. 3, PI. xix. of Lydekker's paper (Tr. Linn. Soc, Zool. vol. viii.) is part of the 

 skull of an Ursus, not of a Procyon as labelled. 



