ANATOMY IN A NUTSHELL 



341 



tricle; as this passage goes forward between the crura cerebri in front, and 

 the corpora quadrigemina behind, it is contracted and is called the aque- 

 duct of Sylvius (iter e tertio ad quartum ventriculum) ; from here it passes into 

 a narrow but high room, called the third ventricle, which is between the optic 

 thalami; these two ventricles are in the median line of the brain. There are 

 two lateral ventricles, one in each hemisphere, which are connected with 

 the third one by the foramen of Monro. There is the fifth ventricle not con- 

 nected with the others; it is situated in the septum lucidum. 



The brain consists of four main parts, (1) fore-brain, (2) inter-brain, (3) 

 mid-brain, and (4) hind-brain. The brain is called encephalon; the cerebral 



PLATE CLXI. 



CYSTIC DUCT 



SUPRARENAL 

 CAPSULE 



SPLENIC ARTERY 



ORIFICE OF ACCESSORY PANCREATIC DUCT. 



ORIFICE OF BILE AND PANCREATIC DUCTS 



SUP. MESENTERIC ARTERY 



interior vena cava. 

 Pancreas, Duodenum and Kidney. 



hemispheres are called prosencephalon; the parts around the third ventricle 

 are called the thalamencephalon ; the parts around the aqueduct of Sylvius arc 

 called the mesencephalon; the pons and cerebellum, are called the epencephalon; 



the medulla is called the metencephalon ; the olfactory tract is called the rhin- 

 encephalon. The spinal cord is called the myelon. The encephalon and the 

 myelon constitute the neuron. The brain, like the spinal cord, has three coats. 

 viz., dura mater, arachnoid, and pia mater. The arteries which supply the 

 dura mater are derived chiefly from the anterior, middle, and posterior menin- 

 geal. The nerve supply of the dura mater is the sympathetic,* rasserian ganglion, 

 fourth, fifth, tenth, and twelfth. The arachnoid has but a limited blood sup- 

 ply, and the nerve supply is from the motor division of the fifth, the seventh, 

 and the spinal accessory. The pia mater receives blood supply from the ni- 



