§ 4 INNERVATION OF HYPOPHYSIS 67 



longitudinalis, thus forming a connexion with the medulla. 

 Nerves entering the stalk laterally from the lobi inferiores of 

 the hypothalamus can be followed for a brief distance only; 

 they, however, connect up with tracts running upwards 

 towards the tectum opticum. 



c. Central autonomic centre (Fig. ^4 B.) 



Holmgren (1920) and Scharrer (1936) found in the 

 brain of amniotes, central autonomic nuclei, whose ganglion 



-— ^ir"-iy 



nucl. mcgnocelL-'' 

 preaopt. 





sex-cen 

 nucl. lateralis tuberiz (Z^t^'"^ 



B. Central sympathetic nucleus. 



Fig. 54B. Innervation of the hypophysis in Rhodeus amarus; 

 central autonomic centre. 



cells had changed into secreting cells, and might therefore 

 have a neurocrinal action. In the neighbourhood of the hypo- 

 physis there is such a nucleus, the nucleus lateralis tuberus. 

 Bretschneider found this nucleus also in the bitterling. It 

 extends in the form of a row of very large cells on either side 

 of the hypophysial stalk. As SCHARRER observed, these nuclei 

 contain large cells of various shapes. There is no indication, 

 however,* of any neurocrine function in the bitterling, and 

 in none of our preparations from animals at any season or 

 after any experiment could we find any indication of the 

 production of secretions. On the contrary, we found thick 

 processes coming from these large cells and penetrating into 

 the pituitary stalk, there to join other nerves of more remote 

 origin. These cells also contain NisSL-substance and are clearly 

 nerve cells. 



In front of the nucleus lateralis tuberus is a group of cells 

 from v/hich the tracts passing to the hypophysis appear to 



