382 



ANATOMY OF THE CENTEAL NEEVOUS SYSTEM. 



fibers from the cord have entered the restiform body. Likewise it receives 

 there a portion of the olivary tract. The inferior cerebellar peduncle lies 

 to the side of the last remnant of the posterior columns, forming a thick 

 bundle. 



We have here a cross-section typical of the medulla.^ After knowing the 

 single component parts of this section it will be well to consider them all 

 together. Much additional will appear thereby (Fig. 243). 



Ventrally lie the pyramids. The long triangular bundle of fibers, cut 

 across just behind the pyramids, is the lemniscus (fillet), the decussated pro- 

 longations of the posterior nerve-roots. The nuclei of the posterior columns 



Fig. 243. — Section through the medulla oblongata. Aufsteigende Tagus, 

 etc., TT., Ascending root of vagus, etc. Tord. Tag., etc., ~W., Anterior root of 

 vagus, etc. Hint. Ldngsb., Posterior longitudinal fasciculus. Aufst. Trigem. 

 Wurz., Ascending root of trigeminus. 8eit. Str. B., Lateral cerebellar tract. 

 Central Haul). B., Central tegmental tract. Oliv. Zwisoh. SchioM, Interolivary 

 layer. Hint. Neb. Olive, Posterior accessory olivary body. Innere Neb. Olive, 

 Inner accessory olivary body. 



lie posteriorly and laterally, covered only by a few nerve-fibers. Numerous 

 fibras arcuatse interuEe arise there and crowd through the space between the 

 posterior horns and the fillet to the raphe, and so to the other side. 



A similar course is taken by the cerebello-olivary fibers. In the figure 



