464 PHYSIOLOGICAL SERIES. 



of the brain the temporal and the parieto-frontal opercula 

 have heen removed so as to expose the whole of the external 

 surface of the island of lleil. If the central lobe of this 

 brain is compared with that of a healthy adult human 

 cerebrum, or that of the Chimpanzee (see specimen 

 D. 673), it will be seen how small and ill-developed the 

 island of Reil is in this microcephalic cerebrum. The 

 marked deficiency in the weight of this human cerebrum, 

 its defective orbital and fronto-parietal opercola, together 

 with the anatomical characteristics of the island of Keil, 

 place it among 1 trains of the Simian type. 



With the exception of the remarkable imperfections in 

 this brain above referred to, its various external fissures 

 and convolutions, although simple in character, do not .differ 

 essentially from those of the average adult human cerebrum. 



The individual to whom this brain belonged is reported 

 to have been a well-behaved lad when left alone, though 

 mischievous ; but under provocation was passionate and 

 uncontrolled, lie was called, from his appearance (*'. ., 

 large coarse features and long arms), " The Monkey hoy," 

 and knew those who treated him well, following them about 

 like a dog, with a peculiar gait. He was incapable of 

 articulate speech, but expressed his wants by noises and 

 signs. Music had a great attraction for him and he could 

 imitate the actions of playing the violin or trumpet. He 

 liked to be taken notice of by visitors, and. when askel. 

 would show off certain tricks he had learnt, as, for instance, 

 imitating the action of playing cricket. His habits were 

 dirty at times. 



D. 684. A cast of the brain of a Microcephalic Idiot. 



D. 685. The brain of C. Babbage, Esq., F.K.S., a distinguished 

 mathematician and inventor. The brain (with the pia 

 mater) weighed 49J ozs. (140G grins.) immediately after 

 removal. 0. C. 1339 A a. 



A full description of the human brain does not come within the 

 scope of this Catalogue. This the student will find in text-books of 

 Human Anatomy. 



