2(i{S Mr. H. I. r.,cock on the 



middle of the inner wall of the bulla (most of the genera), or 

 set far back only a little way in advance of tbe foramen 

 locei-uiti postiaim {Ci/uictis). In some Felidje (e. ff., a skull 

 of F. jiiyiiaroiidi) it is only a little closer to tbe foramen 

 luceruin /JostUuin tban in Cynictis. In otbers it lies back so 

 as to open within that fossa. 



(2) In the Viverridie tbe canal itself may be a long com- 

 pletely bony tul)e traversing the wall of tbe bulla {MvHf/os and 

 allied genera), or it may be a complete bony tube only at its 

 anterior end and an open channel in the bulla posteriorly 

 {Genetta, Puyvnia), or it may be an iiicomi)lete tube or 

 an open ebaunel throughout its length in the bulla [Civettidis, 

 Viverricuta, Viverra), or it may form a very distinct ridge 

 running obliquely across tbe cavity of the bulla {Cynogale) . 

 In the Fclidie it is, as a rule, an open channel, only excep- 

 tionally being a closed bony tube in its posterior half. 



(3) In the Vivcrridse the orific(?'by which the artery enters 

 the base of the skull after leaving the tympanic canal may 

 be entirely cut off from tbe rest of the foramen lacerum 

 medium and fully exposed on the basisphenoid {Mangos^ 

 Cryptoprocta^ Fossa, Galidictis, Arctogalidia), or it may be 

 coutinuous with the foramen lacerum medium behind and form 

 a deeper or shallower notch in the basisphenoid, the anterior 

 end of this notch being sometimes plainly visible in front 

 of the bulla {Arctictis, Diplogale, Paradoxurus), sometimes 

 overlapped by it and only visible by looking beneath the 

 bulla {Geneda, Viverricula, Nandinia). In the Felidaj the 

 orifice always notches the basisphenoid, as in the genera just 

 mentioned, but it is never visible from the surface, because 

 the overlying portion of the bulla forms here a bouy contact 

 or fusion with the basisphenoid. 



The combination of these characters — namely, the fusion 

 of the bulla to the basisphenoid and the consequent complete 

 concealment of the foramen lacerum medium by which the 

 internal carotid enters the skull after leaving the bulla — is 

 apparently the only positive feature that can be substan- 

 tiated between the Viverridse and the Felidae so far as the 

 structures under notice are concerned. 



EXPLANATION OF THE PLATES, 

 Platk X. 



Ficj. 1. Base of cranium of Viierricula malacccnsis, with bulla of leftside 

 rt- iuo\ ed and bristles passed through the eustachian tube and the 

 carotid canal of the right side, ov., foramen ovale ; yi, glenoid 

 foramen ; fm., foramen lacerum medium running from the 



fieriotic and deeply notching the basisphenoid ; st., stylomastoid 

 oramen with the fenestra rotunda on its inner side and the 

 fenestra ovalis juat in front ; per., periotic pierced by these two 



