Herrick, Alorpliology of Nervous System. 169 



with the postrhinal lobe of mammals), thence crossing in the 

 anterior commissure precisely as in the opossum. The tracts 

 then lie on either side the ventricle. The suprachiasmic 

 fossa of the third ventricle fuses with the main portion of 

 the ventricle a short distance caudad to the praecommissura. 

 At that point and for some distance caudad these motor 

 bundles lie in the central regions of the thalamus near the 

 ventricles. 



A large number of sensory fibres accumulate in the 

 lateral aspects of the basal lobes and with the olfactory fibres 

 pass into intimate relations with a dense granular nidulus. 

 Apparently receiving numerous fibres from the hippocampus 

 portion of the occipito-basal lobe, which also has a strong 

 tract connecting with the cephalic part of the hemisphere, 

 this compound sensory tract passes, zv it hout crossing, into the 

 lateral regions of the thalamus and, passing in the opposite 

 direction from, bvit nearly parallel to the optic tract, reaches 

 a ventral portion of the thalamus in the cephalic part of the 

 infundibular region. A part of the sensory fibres turn laterad 

 beneath the corpus geniculatum and enter the hypoarium. 

 The motor tracts continue in the central portion of the 

 thalamus. 



A special tract comparable with the fornix was not 

 observed, though some of the fibres passing to the hypoaria 

 might be compared with it. The tract of dark fibres passing 

 from the median part of the infundibular lobe and the dorso- 

 median portion of the hyporaria to niduli beneath Meynert's 

 bundle might be likened to the bundle of Vicq d'Azyr. 



The Gray Matter of the Thalamus. — The thalamus ex- 

 tends somewhat cephalad to the anterior commissure and 

 beneath the latter in the walls of the supra-chiasmic fossa. 

 The cells here are in several series near the ventricle and are 

 of the usual fusiform sort. The peduncles with both sensory 

 and motor tracts pass into the thalamus at its latero-dorsal 

 aspects. Immediately caudad to the point where the pedun- 

 cular connection ceases, a small nidulus of rather Iftrge, pale 



