BASAL GANGLIA OF THE CEREBRAL HEMISPHERE. 



643 



to the nuclei of the oculomotor, trigeminal, and facial nerves, lie close to the genu, and 

 behind these are the fibres which go to the hypoglossal nucleus ; still further back are 

 cerebro-spinal fibres which enter the spinal medulla and end around the motor cells of 

 the anterior column of gray matter. This cerebro-spinal tract has been observed occupying 

 the middle part of the pedunculus cerebri, into which it passes directly -from the internal 

 capsule. 



According to Monakow the posterior limb contains also an important tract of fibres 

 passing from the motor cortex to the red nucleus (fasciculus cerebrorubricus). 



The retrolenticular part of the posterior limb contains : (1) the fibres of the optic 

 radiation as they pass from the lateral geniculate body to establish their connexions with 



Nucleus lentiformis 



Capsula intfrnu (pars lenticulo-thalamica) 

 Nucleus cauclatus 



Capsula interna 

 (pars lenticulos 

 caudate) 



Union of 



lentiform and 



caudate nuclei 



Hypophysis f an 



cerebri ^posterior lobe-- 

 Tuber cinereum ' / /I 

 Corpus mamillare .' / 1 

 Nervus oculomotorius / KT \'.A 

 Basis pedunculi'' / N "/ -* 



Pons' , 



Nervus trigeminus (portio major) ( 

 Nervus trigeminus (portio minor)'' 



Nervus facialis - 

 Nervus intermedius-' 

 Nervus acusticus''' 

 Nervus abducens ** 

 Nervus glossopharyngeus- 



Nervus vagiu 



Pyramiss 



Oliva 



Fasciculus circumolivaris pyramidis- 



Nucleus amygdalae (cut) 



Commissura anterior 

 Stria terminalis 



Capsula interna (pars sublenticularis) 



-Nucleus caudatus 



'Tlialamus 



Corpus geniculatum laterals 

 -Corpus pineale 

 -Corpus geniculatum mediale 

 -Colliculus superior 



Brachium quadrigeminum 

 '"inferius 

 -Colliculus inferior 



Lemniscus lateralis 

 Nervus trochlearis 



Brachium conjunctivurn 



... .Brachium pontls 



-Fossa flocculi 

 .__Crus flocculi 



Nucleus dentatu? 

 "cerebelli 



Corpus ponto-bulbare 



Fasciculus spinocerebellarh 

 -Nervus spinalis 



FIG. 573. DISSECTION EXPOSING THE LATERAL ASPECT OF THE LENTIFORM NUCLEUS OF THE 



LEFT HEMISPHERE. 



the occipital cerebral cortex; (2) the fibres of the acoustic radiation, or those which 



connect the medial geniculate body with the acoustic cortical field in the temporal lobe 



Fig. 572, p. 641, and Fig. 578, p. 650) ; (3) the temporo-pontine tract, which is com- 



osed of fibres which take origin in the middle and inferior gyri of the temporal 



lobe and pass through the sublenticular section of the internal capsule to reach the 



lateral part of the pedunculus cerebri. Through this they reach the basilar part of the 



xms, in the gray matter of which they end. This tract is accompanied by the fasciculus 



temporothalamicus, which has a widespread origin from the temporal and occipital regions 



and passes through the sublenticular part of the internal capsule. 



f the fibres -of the internal capsule are traced upwards they are found to 

 spread out widely from each other in a radiating or fan-shaped manner, as they 



42 a 



