1910-11.] Topography of Cerebral Cortex of Guinea-pig. 
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XXV. — The Topography of the Cerebral Cortex of the Guinea-pig. 
By Williamina Abel, M.D., McCunn Scholar. (From the Physiology 
Department, Glasgow University.) Communicated by Professor 
D. Noel Paton. 
(Read January 23, 1911. MS. received February 6, 1911 ) 
CONTENTS. 
1. Introduction 
2. Literature 
3. Methods . 
4. Histology of Cortex 
5. Results of Electrical Stimulation 
6. Conclusions and Summary ........ 
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1. Introduction. 
This investigation was begun as a result of certain observations made by 
Dr T. Graham Brown, on reflexes in the guinea-pig (45). In various 
experiments he removed parts of the cerebral cortex and found that little 
if any disturbance, either motor or sensory, ensued. It was thereupon 
suggested that an examination should be made of the cortex histologically and 
by electrical stimulation in order to locate the position of the various areas. 
2. Literature. 
Space only allows of the briefest references to some of the numerous 
papers on the question of cerebral structure and localisation. Among the 
earlier workers may be mentioned Fritz and Hitzig (1, 2), Goltz (3, 4), 
Munk (5), Fiirstner (6), and Ferrier (7). These all describe numerous 
investigations made by them on the cerebral cortex of the lower animals, 
and considerable divergence of opinion is noticeable. The writings of Munk 
show that in his opinion the so-called motor area is also a sensory zone. 
Ferrier’s work is extremely interesting, as he describes definite cortical 
centres associated with definite movements in the brains of the rabbit, 
guinea-pig, and rat. In the rabbit the centres for fore and hind limb 
movement, as well as for movements of ear, nose, and facial muscles, are 
described as lying in the middle and posterior thirds of the cerebrum, 
while the centres for eye and mouth movements are placed in the anterior 
