QUATEHNAET FAUNA OP GIBEALTAE. 77 



Since then, however, we have been furnished with abundant materials for the clearing 

 up of what was to him necessarily obscure, and no difRculty now exists in distinguishing 

 between the three existing species of Uycena from their cranial and dental characters 

 alone ; and I may remark that any diiEculty even at that time would have been removed, 

 had Dr. Falconer been acquainted with Dr. Wagner's excellent paper " on the Specific 

 Differences by which H. brunnea is distinguished from //. striata and crocuta, as 

 manifested in the skull and dentition" i. In this memoir, with which I y-as wholly 

 unacquainted at the time when I communicated my paper to the Linnean Society, 

 nearly all that I have remarked was anticipated more than twenty-three years ago. 



The principal cranial and dental characters by which the three existing species of 

 Hycena are distinguished may be briefly stated as under ^ : — 



H. striata and H. hrunnea. so far as regards cranial and dental characters, agree in 

 so many particulars, as upon superficial inspection to be readily confounded. The 

 chief points in which they agree are also those in which they both differ from H. crocuta 

 and its fossil congeners. 



1. In both species the upper tubercular molar is triradicular and tricuspid, and rarely 

 less than 0"-5 in length by 0"-2 in its shortest diameter ; while in H. crocuta and its 

 allies this tooth is normally biradicular and bicuspid, though not unfrequently by 

 abortion or fusion uniradicular or entirely absent, and it is never more than 0"-2 or 

 0"'21 iu length by about 0"-l in the shorter diameter. 



2. In having the three lobes of the upper carnassial tooth (pm. 4 ) subequal in the 

 antero-posterior direction. 



3. In having a more or less distinct accessory point on the inner side of the hinder 

 cusp of the lower carnassial (m. 1). It is true that a minute tubercle (or rudiment, 

 rather, of a similar point) is not unfrequently seen in nearly the same situation in 

 H. crocuta, and perhaps still more frequently in H. spelcea ^ ; but in those species it 

 never assumes any thing like the size it presents in H. striata and H. brunnea, though 

 it is considerably less in the latter species than in the former. Some difference also may 

 be noticed in the exact situation of the accessory point in H. crocuta and spelma, m both 

 which species it is usually situated as it were in a hollow beneath the base, at the inner 

 and hinder border of the posterior cusp, whilst in H. striata and brunnea it rises distinctly 

 on the inner surface of the cusp. 



Other points of agreement between these two species may be noticed, as, for 

 instance, the presence in both of a distinct anterior talon to the second premolar, and of a 



' " Auseinandersetzung der speciflschen Differenzen durch welche sioh die H, hrunnea von der H. striata 

 und crocuta in der Beschaffenheit des Schadels und Gebisses unterscheidet, vom Prof. Dr. A. Wagner," Miinch. 

 Abhandl. iii. p. 609, 1843. 



' linn. Soc. Journal, ix. p. 65. 



* In twelve lower camassials of H. spelcea, from Kent's Cavern and Kirkdale, in the national collection, a 

 small accessory point was noticed in five, whilst in seven there was merely a trace of one. 



VOL. X. — PART II. No. 4. — August 1st, 1877. M 



