390 



ANATOMY FOR NURSES [Chap. XIX 



There is one of each in each 

 hemisphere. For location see 

 Figs. 185 and 186. 



(3) Fissure of Rolando, or^ 



central fissure. 



(4) Fissure of Sylvius. 



(5) Parieto-occipital fissure. ^ 

 Lobes of the cerebrum. — The longitudinal fissure divides the 



cerebrum into two hemispheres, and the transverse fissure divides 

 the cerebrum from the cerebellum. The three remaining fissures 

 divide each hemisphere into five lobes. With one exception these 



Fig. 186. — Mesial View of Left Cerebral Hemisphere, showing Ro- 



LANDIC AND PaRIETO-OCCIPITAL FiSSURES, TOGETHER WITH THE PRINCIPAL 



Convolutions. (Collins.) 



lobes were named from the bones of the cranium under which they 

 lie ; hence they are known as : — 



(1) Frontal lobe. 



(2) Parietal lobe. 



(3) Temporal lobe. 



(4) Occipital lobe. 



(5) Central lobe, or Island of Reil (the exception). 



(1) The frontal lobe is that portion of the cerebrum lying 

 in front of the fissure of Rolando, and usually consists of four main 

 convolutions. 



(2) Parietal lobe is bounded in front by the fissure of Rolando, 

 and behind by the parieto-occipital fissure. 



(3) Temporal lobe lies below the fissure of Sylvius and in front 

 of the occipital lobe. 



