﻿40 PLEISTOCENE MAMMALIA. 



mission of the maxillary portion of the trigeminal, and more widely separated and exactly 

 opposite the glenoid cavity is the foramen ovale {g), which transmits the infra-maxillary, 

 or mandibular branch of the fifth pair. 1 The latter is called the carotid foramen by 

 M. de Blainville 2 and some others, in the mistaken belief that it transmits the carotid 

 artery. 



The foramen caroticum is in all the Eeles extremely small ; and the external orifice 

 being entirely covered by the Eustachian process of the bulla, and generally, but not 

 always, surrounded by the substance of that portion of the tympanic, it may be said to be 

 within the foramen lacernm medium, immediately on the inner edge of the groove for the 

 Vidian nerve. The internal orifice which is immediately in front of the apex of the 

 petrosal proper leads directly to the groove for the artery described above as on the 

 cerebral surface of the basisphenoid. This is very distinct in the smaller cats, but is less 

 so in the larger. The foramen itself is larger in the jaguar than in any other large Eelis 

 that we have examined, admitting a small wire. It is very small in the tiger, and still 

 smaller in a panther, and even in very young lions • in some old animals of both these 

 species it appears to be entirely closed. In Fells spelaa it closely resembles the lion. 



The functions of the carotid artery, as it exists in most other mammalia, appear to be 

 supplemented, or rather replaced, by those of the numerous vessels which accompany the 

 nerves in their passage through the different foramina, and which in this part of the skull 

 unite an external "rete mirabile" to an internal, for the supply of blood to the brain. We 

 have observed in many skulls of Felis that the large foramina of the alisphenoid are 

 accompanied by smaller, which appear to be appropriated to the transmission of vessels, 

 though we have not ascertained this to be the case by the actual dissection of those spe- 

 cimens. 



Muscles. — The hamular processes of the pterygoidal portion of the alisphenoid being- 

 broken away, we can say nothing of the origin of the constrictor superior pharyngis, or of 

 Folian muscle, in Felis sjjelaa. The origin of the circumflexus 3 (Albinus) is under the 

 foramen ovale ((/), whence it passes round the hamular process to its insertion in the 

 velum palati. 



§ 6. Presphenoid and Orbito-sphenoid (PI. VIII, fig. 9). — All that hold the "vertebral 

 theory" of the skull agree in assuming the homologies of the centrum of a vertebra for some 

 part of the presphenoid, though there are differences of opinion as to the morphological 

 value of the different parts. The bone is firmly anchylosed to the orbito-sphenoid while still 

 foetal, and the sutures have all but disappeared at birth ; for this reason we describe them 

 as one bone. 



1 Straus-Durekheim, op. cit., vol. i, p. 295. Holden, ' Human Osteology,' p. 395. 



2 'Osteol. Felis,' p. 14. 



3 Straus-Durekheim, op. cit., vol. ii, p. 229. 



