510 



THE BLOOD-VASCULAR SYSTEM. 



The anterior cerebral arises from the internal carotid at the inner extremity 

 of the fissure of Sylvius. It passes forward and inward across the anterior perfo- 

 rated space, above the optic nerve, to the commencement of the great longitudinal 

 fissure. Here it comes into close relationship with the artery of the opposite side, 

 and the two vessels are connected together by a short anastomosing trunk, about 

 two lines in length, the anterior communicating artery. From this point the two 

 vessels run side by side in the longitudinal fissure, curve round the genu of the 

 corpus callosum, and, turning backward, continue along its upper surface to its 

 posterior part, where they terminate by anastomosing with the posterior cerebral 

 arteries. In their course they give off the following branches : 



Antero-median ganglionic. Anterior internal frontal. 



Inferior internal frontal. Middle internal frontal. 



Posterior internal frontal. 



The antero-median ganglionic is a group of small arteries which arise at the 

 commencement of the anterior cerebral artery ; they pierce the anterior perforated 

 space and lamina cinerea, and supply the head of the caudate nucleus. 



Anterior 

 Orbital 

 Convolution 



FIG. 294. Vascular area of the inferior surface of the cerebrum. ^After Duret.) I. The part supplied by 

 the anterior temporal artery. II. The part supplied by the posterior temporal artery. III. The part supplied 

 by the occipital artery. 



The inferior internal frontal, two or three in number, are distributed to the 

 orbital surface of the frontal lobe, where they supply the olfactory lobe, gyms 

 rectus, and internal orbital convolution. 



The anterior internal frontal branches supply a part of the marginal convolu- 

 tion, and send branches over the edge of the hemisphere to the superior and 

 middle frontal convolutions and upper part of the ascending frontal convolution. 

 The middle internal frontal branches supply the corpus callosum, the convolution 

 of the corpus callosum, the inner surface of the first frontal convolution, and the 



