24? Dr. Foville on the Anatomy of the Brain. 



and at the basilary surface ; and lastly, from those which in 

 the fissure of Sylvius itself constitute the lobule of the insula. 

 Of the convolutions of the regions which I have just pointed 

 out, those of the internal aspect of the cerebello-temporal 

 zone are included between the line of convolutions which 

 tracks the large circumference of the hemisphere, and that 

 part of the convolution of the border which extends from 

 the anterior to the posterior margin of the perforated qua- 

 drangle, following the curve from before to behind of the 

 corpus callosum, and the fissure of Bichat. Lastly, the 

 convolutions of the insula are included between the line of 

 convolution forming the inclosure of the fissure of Sylvius, 

 and that part of the convolution of the border, very short in 

 man, on which is prolonged the external root of the olfactory 

 nerve. 



If we dissect the convolutions of the plain internal surface 

 of the hemisphere, those of the cerebello-temporal zone, and 

 lastly, those of the insula, we can easily show that their fi- 

 brous parts converge from the great circumference of the 

 hemisphere, and of the convolutionary inclosure of the fissure 

 of Sylvius towards the corresponding regions of the convolu- 

 tion of the border, and terminate at last in the fibrous band 

 of the border itself, whose connexions with the perforated 

 quadrangle, the sensorial nerves of the brain, and the posterior 

 parts of the spinal marrow we are already acquainted with. 

 On the contrary, dissection of the convolutions on the ex- 

 ternal convex surface of the hemisphere included between the 

 two grand lines of convolution which bound this aspect, one 

 of these lines traversing the great circumference of the brain, 

 the other following and forming the boundar}' of the fissure 

 of Sylvius, shows that the fibrous twig of these convolutions 

 terminates in the plane of the hemisphere which emanates 

 from the pyramidal portion of the cms cerebri. 



As to the two lines of convolution situated on the limit of 

 those convolutions which are united with the dependences of 

 the border and of those which envelope the terminations of 

 the plane of the hemisphere, they both pertain by one of their 

 margins, to the productions of the border, and by the other 

 to the productions of the plane of the hemisphere. They 

 form then a means of union between the two orders of con- 

 volutions, of which the one is connected to the sensorial nerves 

 and the posterior parts of the spinal marrow, and the other 

 to the anterior pyramids and the anterior parts of the spinal 

 marrow. 



Thus all the convolutions developed in the interval of the 

 two spaces between the external surface of the hemisphere 



