METATHALAMUS AND HYPOTHALAMUS. 



373 



form, however, the only elements of the medulla of the regie subthalamica. 

 In the section from the dog, shown in Fig. 176, which falls somewhat farther 

 frontally than Pig. 175, and also subsequently in Fig. 178, you see large 



Kg. 176. — From the dog. Frontal section through about the middle of the 

 thalamus. Beneath the corpus callosum lie the frontal ends of both cornua 

 Ammonis, which are connected by means of the psalterium, and send out the 

 immense fimbria on each side. In the thalamus: the nucleus medialia and 

 lateralis in their greatest expanse, separated from one another by the lamina 

 medullaris interna, cut transversely; bounded dorsally by the taenia thalami, 

 into which fibers pass from the stratum zonale, bounded by the posterior part 

 of the nucleus anterior and the dorso-frontal ganglion of the ganglion habenulae. 

 Lateral and dorsal, the tail of the nucleus caudatus and its association-bundle. 

 From the capsula interna enters the corona radiata of the nucleus lateralis 

 and of the nucleus anterior; between the nucleus lateralis and the capsula in- 

 terna there develops from the first the lamina medullaris externa. At the base, 

 the corpus mamillare, in which, at the level of this section, the bundle of Vicq 

 d'Azyr from the nucleus anterior and the tegmental bundle enter united. Lat- 

 erally there develops the pedunculus mamillaris; dorsally, directly beneath the 

 ventricle, the decussatio subthalamica anterior. The capsula interna lies exposed 

 on the under surface as the pes pedunculi; its most mesial fibers here arise from 

 the forebrain-bundle and end in the corpus Luys. Dorsal to the corpus Luys the 

 libers of the deep olfactory medulla, and, lying close to these, the radiatio thalami 

 ventralis. Lateral to the capsula interna, the lenticular nucleus, from which the 

 ansa lentiformis applies itself closely to the pea. Between the ansa and the 

 ventral part of the eornu Ammonis, the nervus opticus. 



Bas. 7. Eirn Bdl., basal forebrain-bundle. GittersoMcht, latticed layer. 



