342 



ANATOMY IX A NUTSHELL. 



ternal carotid and vertebral arteries. The nerve supply is from the sympathetic, 

 the third, fifth, sixth, seventh, ninth, tenth, and eleventh cranial nerves. 



The exterior of the cerebrum is uneven, having hills and valleys. The hills 

 are called gyri, or convolutions; the valleys are called sulci, or Assures. The 

 larger fissures are called primary, the others secondary. The primary are 

 either complete or incomplete. A complete Assure makes an impression in a 

 ventricle of the brain. They are all on the mesial surface of the brain. They 

 are (1) the dentate, which makes the hippocampus major in the descending 

 lioiii ; (2) the ealcarine, which makes the hippocampus minor in the posterior 



PLATECLXII. 



UUCTUS VENOSUS FISSURE 

 LEFT LOBE 



RIGHT LOBE 

 VENA CAVA FISSURE 



UM B,LICAL FISSURE -GALLBLADDER F.-SSl). 



Lobes and Fissuses of the Liver. 



horn; and (3) the collateral, which makes the eminentia collaterals in the de- 

 scending horn. There are two others which are sometimes called complete 

 fissures, the transverse, which has opposite it the choroid plexus, and the 

 fissure of Sylvius, which has opposite it the corpora striata. The last two 

 are not on the mesial surface. 



LESSON XCVIII. 



The right and left lobes of the cerebrum are connected by the corpus 

 CALLOSUM. There are five lobes in each hemisphere of the brain. 



The brain is the encephalon; the part of the cerebro-spinal axis which is 

 contained in the cranium. Its divisions are the cerebrum or brain proper, the 

 cerebellum or little brain, the pons Varolii, and the medulla oblongata. The 

 average weighl of the brain in the male is forty-nine and one-half ounces, in 

 the female forty-four ounces. Cuvier's brain weighed more than sixty-four 

 ounces. The human brain weighs more than that of any other animal, except 

 the elephant and whale. The elephant's brain weighs about ten pounds; that 

 of the whale five pounds. 



Like the bark (cortex) of a tree the cortical layer of the brain covers the 

 surfaces of the brain. It is composed of cellular nerve-material. 



