296 C. JUDSON HERRICK 



specialized form of the same structure; but of the fiber connec- 

 tions of these neurons nothing is known. 



The eminentia suhcerehellaris tegmenti. This is a very large 

 ventricular eminence in the motor tegmentum under the nucleus 

 posterior tecti and cerebellum and extending as far forward as 

 the fovea isthmi (figs. 14, 63, 64, 68, em.s.t.). The dendrites 

 of its neurons are widely spread among the fibers of the motor 

 tegmentum, and especially are directed dorso-laterally into the 

 area of termination of the dorsal fasciculi of the motor tegmen- 

 tum. These dendrites form dense packets between the longi- 

 tudinal fascicles of the motor tegmentum. They receive direct 

 and crossed fibers from the tectum and from regions farther 

 forw^ard by the tegmental fascicles. 



The axons of some of these neurons (chiefly unmyelinated) are 

 directed forward and ventrally parallel with the brachium con- 

 junctivum. These fibers reach the mid-ventral plane within 

 the interpeduncular nucleus immediately caudad of the fovea 

 isthmi and appear to end in relation with the ventro-medial 

 nucleus of the III nerve (the supposed representative of the 

 nucleus of Edinger-Westphal, see p. 235). They are provision- 

 ally named the tractus tegmento-interpeduncularis (p. 272). 



There is a group of very large neurons at the lateral border 

 of the stratum griseum of the eminentia subcerebellaris whose 

 myelinated axons are directed laterad and caudad without de- 

 cussation into the ventral fasciculi of the motor tegmentum of 

 the oblongata, thus constituting a tractus tegmento-bulbaris 

 (p. 271). Other fibers of this system doubtless decussate in 

 the ventral commissure. These fibers put the motor tegmen- 

 tum under the tectum mesencephali into functional relation with 

 the reticular formation of the oblongata. Golgi sections show 

 that the dendrites of these large neurons spread widely through 

 the motor tegmentum, especially caudo-laterally into the emi- 

 nentia ventrahs cerebelli ('14, p. 4), where they come into relation 

 with descending fibers of the dorsal tegmental fascicles and as- 

 cending fibers of the tractus spino-bulbaris ('14 a, p. 375). 

 Large bipolar neurons with widely branched dendrites are 

 occasionally impregnated in the stratum album laterally of the 



