CONNECTIONS OF THE BULB 6ll 



form bodies and go to the cerebellum. The antero-lateral- ascending 

 tracts (Gowers) appear to have the same destination, but pass indirectly into 

 the cerebellum by way of the superior medullary velum; some of the fibers 

 probably pass upward to higher centers. The fibers of the tracts of Goll 

 and Burdach, of the cord, end in the nuclei of the funiculus gracilis and funic- 

 ulus cuneatus, respectively; at any rate, ascending degeneration of these 

 columns cannot be traced above these nuclei. The rest of the fibers of the 

 cord appear to end in the reticular formation of the bulb. 



TT.TZT. . , , n>c 



7*. err. 



FIG. 381. Section of the Medulla Oblongata at about the Middle of the Olivary Body. 

 /./.a., Anterior median fissure; n.ar., nucleus arciformis; p., pyramid; XII., bundle of 

 hypoglassal nerve emerging from the surface; at b, it is seen coursing between the pyramid 

 and the olivary nucleus, o.; f.a.e., external arciform fibers; n.L, nucleus lateralis; a., 

 arciform fibers passing toward restiform body, partly through the substantia gelatinosa, 

 #., partly superficial to the ascending root of the fifth nerve, a,V.; X., bundle of vagus root 

 emerging; f.r., formatio reticularis; c.r., corpus restiforme, beginning to be formed, chiefly 

 by arciform fibers, superficial and deep; n.c., nucleus cuneatus; n.g., nucleus gracilis; *, 

 attachment of the ligula;/.s., funiculus solitarius; n.X., Xn..', two parts of the vagus nucleus; 

 n. XII., hypoglossal nucleus; n.t., nucleus of the funiculus teres; n.am., nucleus ambiguus; 

 r., raphe; A., continuation of the anterior column of cord; o',o", accessory olivary nucleus; 

 P.O., pedunculus olivas. (Modified from Schwalbe.) 



Connections of the Bulb with the Cerebrum and Cerebellum. The 



pyramidal tracts connect the bulb with the cerebrum; and the direct cere- 

 bellar and the antero-lateral ascending tract, tract of Gowers, connect it with 

 the cerebellum. Other connections of the bulb with the cerebrum and with 

 the cerebellum are: 



i. Fibers from the nucleus gracilis and nucleus cuneatus, which, as we 

 have said, are the endings of the fibers of the tracts of Goll and Burdach 

 of the cord, pass in sets in the following manner: 



a. Internal arcuate fibers pass down and inward to the opposite side in 

 the reticular formation, composing in part the superior or sensory decussation, 



