MOTOR NUCLEI IN PHYLOGENY 245 
ae 
ay S. 
ey = 
ZP \ Nu NT. mv 
\Nu. Vim. d. 6 
Fig. 5 Cacatua roseicapilla. Transverse section through the medulla at the 
exit level of the motor facial root. R. VI, fifth emergent abducens rootlet. 
Fig. 6 Cacatua roseicapilla. Transverse section through the medulla at the 
exit level of the third abducens rootlet (R. VJ.). Figures 5 and 6 at the same 
magnification as figure 1. 
F.s., fasciculus solitarius; Nu. parv. VIII. v., small-celled vestibular nucleus 
(Brandis, 14); Nu. VZ., abducens nucleus; Nu. VII. m.d., dorsal motor facial 
nucleus (= caudal part of motor V-VII nuclear complex); Nu. VII. m.v., ventral 
motor facial nucleus; NV. VI//. v., vestibular root; O.s., superior olive; R. desc. V., 
radix descendens trigemini; R. V/T., root fibers of the facial nerve; R. VII. m., 
intramedullary motor facial fibers; Vent., fourth ventricle. 
