122 



THE NERVOUS SYSTEM 



gracilis and nucleus cuneatus, within which end the fibers of the corresponding 

 fasciculi of the spinal cord. The clava and cuneate tubercle are displaced lat- 

 erally by the caudal angle of the fourth ventricle. Somewhat rostral to the mid- 

 dle of the medulla oblongata they gradually give place to the restiform body. 



More laterally, between the cuneate funiculus and tubercle on the one hand 

 and the roots of the glossopharyngeal, vagus, and accessory nerves on the other, 

 is a third longitudinal club-shaped elevation called the tuber culum cinereum. 

 It is produced by a tract of descending fibers, derived from the sensory root of 

 the trigeminal nerve, and by an elongated mass of substantia gelatinosa which 



Corona 



Lentiform nucleus 

 Lateral geniculale body v 

 Medial geniculale body 

 Optic radiation \ 

 Corona radiata , 

 Pulvinar\ 



Inferior quadrigeminal brachium^* 



Superior colliculus - v 



Trochlear nerve O 



Inferior colliculus-^ 



Brachium pontis'*- 



Brachium conjunctivum'' 



Restiform body 



Acoustic nerve 



\ Cochtear n _ 



Dorsal cochlear nucleus 



Glossopharyngeal nerve - 



Vagus nerve and restiform body 



Accessory nerve " - 



Clava'"" . 



Cuneate tubercle'"' 



Anterior perforated substance 



Optic tract 



Optic nerve 



Infundibulum 



Mammillary body 



Hypophysis 



'Oculomotor nerve 



" Transverse peduncular tract 



Cerebral peduncle 



Pans 



Abducens nerve 



Trigeminal nerve 



Facial nerve 



Trapezoid body 



'* Olive 



" Tractus later alis minor 



Hypoglossal neme 



Fig. 87. Lateral view of brain stem of the sheep. 



forms one of the nuclei of this nerve (Fig. 111). This bundle of fibers and the 

 associated mass of gray matter are known as the spinal tract and nucleus of the 

 spinal tract of the trigeminal nerve. 



The restiform body (corpus restiforme or inferior cerebellar peduncle) lies 

 between the lateral border of the fourth ventricle and the roots of the vagus 

 and glossopharyngeal nerves in the rostral part of the medulla oblongata (Figs. 

 87-89). There is no sharp line of demarcation between it and the more cau- 

 dally placed clava and cuneate tubercle. It is produced by a large strand of 

 nerve-fibers, which run along the lateral border of the fourth ventricle and then 

 turn dorsally into the cerebellum. These fibers serve to connect the medulla 



