94 equine anatomy. 



4. Crura cerebelli. 

 die is the largest; the posterior tne sii^aiiest f tney cim^/ 



dh-ectly into the cerebellum. ' ^ ^y^ZJi^^^^^^^^^f!^^ 



5. Yalve of Vieussens. — Thin lamella, uniting the / 

 two anterior cerebellar peduncles. 



6. Corpora quadrigemina. — Anteriorly the tuber- 

 cula nates, and posteriorly the testes uniting outwardly 

 to the corpus geniculatum externum. 



7. Thalami optici. — Inclined inwardly to form a 

 deep fissure containing the anterior peduncles of the 

 pineal gland ; this fissure presents at its extremities 

 the anterior and posterior common openings ; outward- 

 ly shows the corpus geniculatum externum and inter- 

 num ; in front it exhibits the semi-circular band or taenia 

 semi-circularis. 



8. Pineal gland or conarium. — Reddish-brown 

 mass resting on the posterior common opening. 



9. Pituitary gland. — Synonyms. Hypophysis cer- 

 ebri, supra sphenoidal appendage ; fixed to the inter- 

 pedunculum fissure by the pituitary stem and tuber- 

 cinereum. 



(h.) Internal conformation. — Three cavities. 1. — 

 Middle ventricle of the thalami optici. Division : Two 

 walls, a floor, a roof with the anterior and posterior 

 common openings separated by the grey commissure. 

 The posterior extremity is continuous with the aque- 



