366 LABORATORY MANUAL OF HUMAN ANATOMY 



Like the sensory spinal nerves, the sensory cerebral nerves arise 

 from ganglia outside the central nervous system and their axones 

 terminate in certain end-nuclei (nuclei terminates) inside the 

 central system; in these end-nuclei are cells which give off the 

 axones of secondary fibre systems. 



OLFACTORY NERVES (NN. OLFACTORII). 



Nuclei originis: bipolar cells of regio olfactoria of nasal mucous mem- 

 brane. 



Nuclei terminates : in olfactory glomeruli of bulbus olf actorius. 

 Secondary path: from mitral cells of bulbus olf actorius through tractus 

 olfactorius to 



(a) Gray matter of trigonum olfactorium. 



(b) Through stria olfactoria lateralis to uncus and thence to hippo- 



campus and gyrus cinguli. 



(c) Through stria olfactoria intermedia to substantia perforata ante- 



rior. 



(d) Through stria olfactoria medialis to gyrus subcallosus. 



BIPOLAR CELLS OF RETINA (analogous, for visual path, to sensory fibres of pos- 

 terior roots of spinal nerves). 

 Nuclei terminates: ganglion cell layer of retina, 



Secondary path: from ganglion cell layer of retina, through (badly 

 named) N. OPTICUS, chiasma opticum, and tractus optici, to 



(a) Corpus geniculatum laterale. 



(b) Pulvinar thalami. 



(c) Superficial and middle gray strata of superior colliculus of corpora 



quadrigemina. 

 Tertiary paths: 



(a) From corpus geniculatum laterale and pulvinar thalami, through 



radiato occipitothalamica [Gratioleti], to cortex of occipital lobe 

 about the fissura calcarina. 



(b) From middle gray layer of colliculus superior, through decussatio 



tegmenti dorsalis of Meynert and fasciculus longitudinalis me- 

 dialis of opposite side, to eye-muscle nuclei and spinal cord ; this 

 is the so-called "optic-acoustic reflex path" (Held), 



OCULOMOTOR NERVE (N. OCULOMOTORIUS). 



Nuclei originis: nucleus of oculomotor nerve (nucleus N. oculomotorii) 



in tegmentum of cerebral peduncle. 

 Cortical control: 



(a) From cortex of central gyri through capsula interna (?). 



(b) From cortex about fissura calcarina to superior colliculus and then 



through optic-acoustic reflex path. 



TROCHLEAR NERVE (N. TROCHLEARIS). 



Nucleus originis: nucleus of trochlear nerve (nucleus N. trochlearis) in 



isthmus rhombencephali on opposite side, through decussatio nervorum 



trochlearium. 

 Cortical control: probably same as for N. oculomotorius. 



