572 



THE ARTERIES. 



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

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



The anterior and internal frontal branches supply the two inferior frontal 

 convolutions. The middle and internal frontal branches supply the corpus 

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

 frontal convolution, and the upper part of the ascending frontal convolution. The 

 posterior and internal frontal branches supply the lobus quadratus. 



The anterior communicating artery is a short branch, about two lines in 

 length, but of moderate size, connecting together the two anterior cerebral 



Fissure of Rolando. 



/*" 



FIG. 355. Vascular arese of the internal surface of the cerebrum. (After Charcot.) The regions marked off 



by the line ( ) represent the area of distribution of the anterior cerebral artery : I. Anterior and internal 



frontal arteries. II. Middle and internal frontal arteries. III. Posterior and internal frontal arteries. The 



regions marked off by the line ( ) represent the area of distribution of the posterior cerebral 



arteries : IV. to the temporo-sphenoidal lobe ; V. to the cuneus and occipital lobe ; a third branch supplies the 

 uncinate gyrus. 



arteries across the longitudinal fissure. Sometimes this vessel is wanting, the 

 two arteries joining together to form a single trunk, which afterward divides. Or 

 the vessel may be wholly or partially divided into two ; frequently it is longer 

 and smaller than usual. It gives off some of the antero-median ganglionic group 

 of vessels, which are, however, principally derived from the anterior cerebral. 



The middle cerebral artery (Fig. 356), the largest branch of the internal car- 

 otid, passes obliquely outward along the fissure of Sylvius, and opposite the island 

 of Reil divides into its terminal branches. The branches of the middle cerebral 

 artery are 



Antero-lateral Ganglionic. 

 External and Inferior Frontal. 



Ascending Frontal. 

 Ascending Parietal. 



Parieto-sphenoidal. 



The antero-lateral ganglionic branches are a group of small arteries which 

 arise at the commencement of the middle cerebral artery ; they pierce the ante- 

 rior perforated space and supply the greater part of the caudate nucleus, the len- 

 ticular nucleus, the internal capsule, and a part of the optic thalamus. One 

 artery of this group, distributed to the lenticular nucleus, is of larger size than 

 the rest, and is of special importance, as being the artery in the brain most fre- 

 quently ruptured; it has been termed by Charcot the "artery of cerebral haemor- 

 rhage." The external and inferior frontal supplies the third or inferior frontal 

 convolution (Broca's convolution). The ascending frontal supplies the ascending 

 frontal convolution. The ascending parietal supplies the ascending parietal con- 



