THE COMMON CAROTID ARTERIES. 677 



8. A fine tympanic arteriole. 



4. The spheno-spinous artery, almost entirely destined to the formation of the plexus of the 

 cerebral arteries. 



5. Several pteryynid arteries. 



6. The ophthalmic artery, which, before entering the ethmoidal fossa by the orbital foramen, 

 gives, independently of the branches noted in Solipeds— except the supra-orbital, which is 

 absent— a fasciculus of particular branches. These penetrate the cranium by the great sphe- 

 noidal fissure, accompanying the motor and sensory nerves of the eye, to join the internal 

 carotid and spheno-spinous arteries. 



7. The anterior deep temporal artery. 



8. A staphyline artery, more voluminous than that in the Horse. 



9. The palatine artery. 



10. A buccal and an alveolar artery, the principal divisions of which enter Duvernoy's 

 gland. 



b. The superior dental artery, which terminates the internal maxillary, and furnishes an 

 orbital and an infra-orbital branch, as in Solipeds. The latter, remarkable for its volume, 

 emerges from the superior dental canal with the infra-orbital nerves, to join the divisions of the 

 external maxillary artery on the face, and in the tissue of the upper lip. 



2. Carotid Arteries in the Pig. 



There is nothing particular to notice regarding the course of these vessels, which we know 

 arise separately from the axillary artery. 



Occipital Artery. — In its (listiibution,it greatly resembles the same vessels in the Horse 

 and Dog. Its most important branches are the following : 1. A very small retrograde artery, 

 anastomosing with tlie vertebral. 2. A branch which ascends into the muscles of the neck, 

 representing the mastoid artery. 3. Several occipital arterioles, which pass, with the principal 

 artery, by the anterior foramen of the atlas. This artery is expended in a complete manner in 

 the muscles of the neck, and without sending a cerebro-spinal branch to the interior of the 

 spinal canal. 



Internal Carotid Artery. — After furnishing a large meningeal artery, this vessel enters 

 the cranium by the foramen lacerum basis cranii, and there divides to form a rete mirabile, analo- 

 gous to that of Ruminants, and of which a description will be given hereafter. The cerebral 

 arteries arising from this r^seau differ but little from those of Solipeds ; these are the posterior 

 cerebral arteries, which give rise to the basilar artery and originate the middle spinal artery. 



External Carotid Artery.— This artery is seen to pass between tjje pterygoid muscles and 

 the branch of the maxilla, in describing several inflections, and arrives in the maxillary hiatus, 

 without exhibiting in its course any sensible distinction between the external carotid, properly 

 called, and its continuation, the internal maxillary artery. 



Among the branches it supplies, we notice : 



1. The lingual artery, more voluminous, perhaps, than in the other animals. 



2. A branch analogous, in its origin at least, to the glosso-facial artery of the Horse, and 

 •which distributes its ramuscules in the submaxillary space, and particularly to the salivary 

 and lymphatic glands. 



3. The posterior auricular artery, noticeable for its great length and considerable volume. 



4. The transverse artery of the face and the anterior auricular artery, arising separately 

 beside each other, and extremely slender. 



5. Several deep temporal and masseteric arteries. 



6. Pterygoid branches. 



7. An enormous buccal branch. 



8. The ophthalmic artery, concurring to form the rete mirahile. 



9. A small orbital branch, coming from the superior dental artery in Solipeds and Carnivora. 



10. The nasal, palatine, and superior dental arteries. 



3. Carotid Arteries of Ruminants. 



A. In the Sheep, which will serve as a type for this description, the carotid arteries arise 

 by a common trunk from the right axillary artery, as in Solipeds. Arriving in the cephalic 

 region, towards the upper part of the neck, they furnish a thyroid and a laryngeal branch, then 

 give off a very slender occipital artery, and are continued from this point by the external 

 carotid. 



The internal carotid, properly called, is absent, and we shall see immediately how it is com- 

 pensated for. 



Occipital Artery.— Having given some ramuscules to the anterior straight muscles of the 



