1408 



A MANUAL OF ANATOMY 



The floor presents a prominent swelling, which is the large round 

 extremity of the nucleus caudatus of the corpus striatum. 



The posterior cornu has its roof and outer wall formed by the 

 tapetum of the corpus callosum. The inner wall presents two 

 elongated, curved eminences, upper and lower. The upper eminence 

 is produced by the fibres of the forceps major as they sweep back- 

 wards from the lower part of the splenium of the corpus callosiun 

 to the occipital lobe. It is called the bulb of the posterior cornu. 

 The lower eminence is called the calcar avis or hippocampus minor, 



Descending Cornu 

 Hippocampus Major. 



Trigonum Ventriculi' 



Pes Hippocampi 



--Uncus 



Gyrus Dentatus 

 "---Hippocampal Gyrus 



~- Fimbria 



Posterior Pillar of Fornix 



5- Splenium 



Buib of Posterior Cornu 



Hippocampus Minor, 

 or Calcar Avis 



Posterior Cornu 



Fig. 593. — The Descending and Posterior Cornua of the Left 

 Lateral Ventricle (after Hirschfeld and Leveill£). 



(The Descending Cornu has been laid open throughout its entire extent). 



and is produced by the anterior calcarine fissure on the mesial 

 surface of the cerebral hemisphere. 



The middle or descending cornu is situated in the temporal lobe. 

 Its roof is formed chiefly by the tapetum of the corpus callosum, 

 and, at the deep end of the cornu, presents the amygdaloid tubercle, 

 which is produced by a collection of grey matter, called the amyg- 

 daloid nucleus. The narrow part or tail of the nucleus caudatus 

 and the taenia semicircularis are prolonged into the roof, and 

 extend in it as far as the amygdaloid nucleus. The floor of the 

 descending cornu presents the following structures : (i) the hippo- 

 campus major, or cornu Ammonis ; (2) the fimbria or taenia hippo- 



