The larger arteries are shown. The nerve-roots are indicated by Roman
numerals. _P.c._, Chorioid plexus of fourth ventricle; _B.p._,
middle peduncle of cerebellum; _P_, pons; _H_, pituitary body;
_L.p._, pyriform lobe; _A.p._, trigonum olfactorium; _B.o._,
olfactory bulb; _S.r.a._, sulcus rhinalis anterior; _S.r.p._, sulcus
rhinalis posterior; _F.l._, lateral fissure (of Sylvius); _F.l.a._,
anterior branch of lateral fissure; _S.p._, presylvian fissure;
_S.p.n._, anterior presylvian fissure; _S.s._, suprasylvian fissure;
_S.e._, ectomarginal fissure.
]