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joining and augmenting them while passing through this ganglion, 

 for such it really is ; so that they come out increased enough 

 to constitute, on the anterior and outer part, at least two thirds' of 

 the crura cerebri, or, as Gall terms them, the great jibrous bundles 

 of the hemispheres. They contain a large quantity of pulpy sub- 

 stance, and enlarge the most at their superior extremity, where 

 the optic nerve turns round them. Their filaments and bundles 

 leave the great fibrous mass at the anterior or outer side of the 

 optic nerve, and, diverging more and more, form the lower, 

 anterior, and outer convolutions of the anterior and middle lobes, 

 which, with the anterior and outer part of the crura and gan- 

 glion in the mesocephalon, are always in direct proportion to the 

 pyramids. (Cut, p. 311.) 



The corpora olivaria are true ganglia. A large bundle pro- 

 ceeds from each, and ascends with the POSTERIOR bundles of the 

 chorda oblongata among the transverse fibres of the meso- 

 cephalon, like the bundles of the pyramids, but acquiring fewer 

 additional fibres than these from among the pulpy matter. On 

 leaving the mesocephalon, they form the posterior and inner 

 part of the crura cerebri. They acquire their greatest increase 

 on entering the crura, on account of the large quantity of pulpy 

 substance which is there, called locus niger, which, with the fibres 

 it produces, forms the two thalami optici, that are here pretty 

 firm ganglia, and are called the great inferior cerebral ganglia by 

 Gall. The bundles, on leaving the superior part of these ganglia, 

 reunite into fibres less diverging, and then traverse two other 

 ganglia the corpora striata, called by Gall the external masses 

 of the pulpy substance of the great superior cerebral ganglion. Here 

 they acquire another increase, sufficient to enable them to form 

 the posterior lobes and all the superior convolutions of the an- 

 terior and middle lobes (Cut, p. 312.), which are always in direct 

 proportion to the thalami. 



All these fibres of the brain (Cut, p. 312.) are styled by Gall 

 diverging, departing, or apparatus of formation. But those of 

 the two sides, that are united by transverse fibres or commissures, 

 are styled by Gall converging or entering fibres. The mesolobe is 

 the great commissure of the superior convolutions of the hemi- 

 spheres. The inferior convolutions of the anterior lobes are united 

 by what was called the anterior fold of the mesolobe, by the 

 anterior portion of it, which was considered to bend down and thus 

 form the anterior extremity of the lateral ventricles, afterwards 



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