THE BRAIN 



117 



invests the cord. The subarachnoid space of the cord is 

 large, and is imperfectly divided by the ligamentum denticulatum, 

 into an anterior and a posterior portion. The posterior por- 

 tion is further subdivided by the septum posticum, which passes 

 from the posterior fissure backwards to the opposite part of 

 the arachnoid, and contains the larger bloodvessels. Trabe- 

 culse also pass between the nerve-roots and the inner surface 

 of the arachnoid, and between the posterior nerve-roots and 

 the septum posticum. 



THE BRAIN. 



Sylvian aqueduct, 

 crura cerebri. 

 corpora quadri- 



gemina. 

 3rd ventricle, 

 optic thalami. 

 pineal body, 

 posterior perforated 



spot. 



corpora albicantia. 

 tuber cinereum. 

 pituitary body, 

 optic commissure, 

 lamina cinerea. 

 convolutions, 

 fissures. 



corpus callosum. 

 lateral ventricles. 

 5th ventricle, 

 septum lucidum. 

 for nix. 



foramen of Munro. 

 velum interpositum 

 choroid plexuses, 

 corpora striata. 

 claustrum. 

 tasnia semicircularis 

 nucleus amygdalae, 

 anterior commissure. 



